Injector Relay and PCM Driver Circuit

Tiny
CMCLEES
  • MEMBER
  • NISSAN
We have a 1996 Nissan 200sx 1.6 fuel injected motor with approximately 175000 miles on it. We are not getting any pulse to the fuel injectors, but have power on one side of the wiring harness. Everything we read indicates that it is probably a bad injector relay or PCM Driver Circuit. Could anyone tell us the location of the injector relay and if the PCM Driver Circuit is the Computer?
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Friday, August 24th, 2007 AT 11:09 PM

33 Replies

Tiny
RASMATAZ
  • MEMBER
I don't think! You got an injector relay-The PCM driver circuit is responsible for driving the ground circuit On and Off to complete the injector circuit by means of durations. Its in the computer ECCS.
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Saturday, August 25th, 2007 AT 2:12 AM
Tiny
CMCLEES
  • MEMBER
We have switched out the computer (with another used one) and that doesn't work either. Any more ideas?
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Saturday, August 25th, 2007 AT 8:22 PM
Tiny
RASMATAZ
  • MEMBER
Now its time to check the wire end to end for an open circuit after that test the power circuit and ground for a short remember when its disconnected from the ECM and injector the ground and power should not be touching together.

We are not getting any pulse to the fuel injectors, but have power on one side of the wiring harness you got this now check the ground wire all the way to the ECM>could be open or short to ground-The ECM does the grounding of the circuit not engine or body ground.
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Sunday, August 26th, 2007 AT 1:18 AM
Tiny
RASMATAZ
  • MEMBER
Now its time to check the wire end to end for an open circuit after that test the power circuit and ground for a short remember when its disconnected from the ECM and injector the ground and power should not be touching together.

We are not getting any pulse to the fuel injectors, but have power on one side of the wiring harness you got this now check the ground wire all the way to the ECM>could be open or short to ground-The ECM does the grounding of the circuit not engine or body ground.

BTW make sure the computer is grounded properly could be the main problem.

Do a continuity test at ECM pin out 105 black wire to engine ground-no reading you have an open main ground wire to driver.

[/quote:6cb2a9f52d]
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Sunday, August 26th, 2007 AT 1:21 AM
Tiny
CMCLEES
  • MEMBER
We have checked everything. The grounds to the computer are good; the crank sensor is good; we checked the computer for codes and it shows a 55 code and the diagnostics indicate that there is nothing wrong. All of the fuel injectors are grounded; one side works, but the pulsing side doesn't. We have plugged; unplugged; check fuses like five times; we have traced wires; anythin else that we can do. We have replaced the distributor (with another used one). The car will start, but only with starting fluid, or carb cleaner but it won't stay running. Could it be the Cam sensor and, if so, will we still get spark?
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Sunday, August 26th, 2007 AT 5:31 PM
Tiny
RASMATAZ
  • MEMBER
What about the ground wire that goes back to the fuel injector harness is it good. That checks out check the crank angle sensor in the distributor

You sure you have the correct fuel pressure, are you getting fuel all the way up to the fuel rail.

I'll be back
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Sunday, August 26th, 2007 AT 7:08 PM
Tiny
RASMATAZ
  • MEMBER
At the computer disconnect the wire connectors find at the computer pin out 106 the black wire that goes to it -make sure that wire is connected to ground if not your injector will not come On. Thats the ground the computer uses to pulse the injectors. On and off.

Are you following everything I've told you to do. If not you ain't gonna find it and you gonna be throwing parts to it left and right and it ain't gonna work.
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Sunday, August 26th, 2007 AT 7:23 PM
Tiny
CMCLEES
  • MEMBER
We just tried this. 106 has ground; so far we have checked everything. We have checked the crank sensor which we found at the top of the bell housing; the cam sensor, from what we understand, is in the distributor. We have switched out the distributor (with another used distributor). Is there a way to test the crank sensor?
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Sunday, August 26th, 2007 AT 7:53 PM
Tiny
RASMATAZ
  • MEMBER
We just tried this. 106 has ground; so far we have checked everything. We have checked the crank sensor which we found at the top of the bell housing; the cam sensor, from what we understand, is in the distributor. We have switched out the distributor (with another used distributor). Is there a way to test the crank sensor?[/Quote:b1546550f2]

Crank the engine over is the injectors clicking? Better comeback am fixing to go

BTW are you getting spark and correct fuel pressure.
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Sunday, August 26th, 2007 AT 8:28 PM
Tiny
RASMATAZ
  • MEMBER
If it can fire up while feeding it -check the fuel system- check the fuel pump relay/fuel pressure etc.
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Sunday, August 26th, 2007 AT 8:36 PM
Tiny
CMCLEES
  • MEMBER
We just tried this. 106 has ground; so far we have checked everything. We have checked the crank sensor which we found at the top of the bell housing; the cam sensor, from what we understand, is in the distributor. We have switched out the distributor (with another used distributor). Is there a way to test the crank sensor?[/Quote:fdb852d2c2]

Crank the engine over is the injectors clicking? Better comeback am fixing to go

BTW are you getting spark and correct fuel pressure.[/Quote:fdb852d2c2]

The injectors are not clicking.

My son ran the car out of oil. The motor locked up. We had bought a used motor when we bought the car. We changed motors; plugged everything in; etc. The car would not start. Through toubleshooting and with your help, we determined that the injectors are not pulsing. The car will start, but as I stated before, only with carb cleaner or starter fluid, but will not stay started at all. We purchased another used computer; we have plugged, unplugged, and checked every ground wire there is. We have changed the distributor and located the crank sensor. We think that the crank sensor is good, but are not sure. Thank you very much for the help.
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Sunday, August 26th, 2007 AT 8:42 PM
Tiny
RASMATAZ
  • MEMBER
We just tried this. 106 has ground; so far we have checked everything. We have checked the crank sensor which we found at the top of the bell housing; the cam sensor, from what we understand, is in the distributor. We have switched out the distributor (with another used distributor). Is there a way to test the crank sensor?[/Quote:4b3b229a10]

Crank the engine over is the injectors clicking? Better comeback am fixing to go

BTW are you getting spark and correct fuel pressure.[/Quote:4b3b229a10]

The injectors are not clicking.

My son ran the car out of oil. The motor locked up. We had bought a used motor when we bought the car. We changed motors; plugged everything in; etc. The car would not start. Through toubleshooting and with your help, we determined that the injectors are not pulsing. The car will start, but as I stated before, only with carb cleaner or starter fluid, but will not stay started at all. We purchased another used computer; we have plugged, unplugged, and checked every ground wire there is. We have changed the distributor and located the crank sensor. We think that the crank sensor is good, but are not sure. Thank you very much for the help.[/Quote:4b3b229a10]

Do you have a reference voltage on the CPS, try cranking the engine and backprobe the signal wire are you gettin anything.

Checking CPS resistances:

Auto-166-204 ohms @ 77degs F
Manual-423-528 ohms @ " "

Check it and comeback

About the injectors maybe shot -never know. Are you getting fuel all the way to the rail or TBI unit.

Okay why don't you get a noid light and test the injector connectors.

The cam and crank sensors tells the computer the firing order position/the speed and position of the crankhaft-now the computer has to get an ignition signal in order for it to energize the injectors thru the quad driver. Could be when the ECM don't get the ignition signal equals to no injection for the purpose of the unburned fuel collecting in the exhaust to ruin the converter.
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Sunday, August 26th, 2007 AT 9:38 PM
Tiny
CMCLEES
  • MEMBER
We just tried this. 106 has ground; so far we have checked everything. We have checked the crank sensor which we found at the top of the bell housing; the cam sensor, from what we understand, is in the distributor. We have switched out the distributor (with another used distributor). Is there a way to test the crank sensor?[/Quote:f915af5a38]

Crank the engine over is the injectors clicking? Better comeback am fixing to go

BTW are you getting spark and correct fuel pressure.[/Quote:f915af5a38]

The injectors are not clicking.

My son ran the car out of oil. The motor locked up. We had bought a used motor when we bought the car. We changed motors; plugged everything in; etc. The car would not start. Through toubleshooting and with your help, we determined that the injectors are not pulsing. The car will start, but as I stated before, only with carb cleaner or starter fluid, but will not stay started at all. We purchased another used computer; we have plugged, unplugged, and checked every ground wire there is. We have changed the distributor and located the crank sensor. We think that the crank sensor is good, but are not sure. Thank you very much for the help.[/Quote:f915af5a38]

Do you have a reference voltage on the CPS, try cranking the engine and backprobe the signal wire are you gettin anything.

Checking CPS resistances:

Auto-166-204 ohms @ 77degs F
Manual-423-528 ohms @ " "

Check it and comeback

About the injectors maybe shot -never know. Are you getting fuel all the way to the rail or TBI unit.

Okay why don't you get a noid light and test the injector connectors.

The cam and crank sensors tells the computer the firing order position/the speed and position of the crankhaft-now the computer has to get an ignition signal in order for it to energize the injectors thru the quad driver. Could be when the ECM don't get the ignition signal equals to no injection for the purpose of the unburned fuel collecting in the exhaust to ruin the converter.[/Quote:f915af5a38]

The CPS resistance, if we are testing it right, is at 531. It is a manual transmission. We are not sure what you are referring to when you say "backprobe the signal wire". We are getting fuel all the way to the rail. We have checked all of the fuel injectors. The power side is fine; but the pulse side nothing. Would it have something to do with the ignition relay? We don't know what the quad driver is. Is it something that we can check? Thanks again for all the help.
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Sunday, August 26th, 2007 AT 10:35 PM
Tiny
RASMATAZ
  • MEMBER
We just tried this. 106 has ground; so far we have checked everything. We have checked the crank sensor which we found at the top of the bell housing; the cam sensor, from what we understand, is in the distributor. We have switched out the distributor (with another used distributor). Is there a way to test the crank sensor?[/Quote:0781e40c60]

Crank the engine over is the injectors clicking? Better comeback am fixing to go

BTW are you getting spark and correct fuel pressure.[/Quote:0781e40c60]

The injectors are not clicking.

My son ran the car out of oil. The motor locked up. We had bought a used motor when we bought the car. We changed motors; plugged everything in; etc. The car would not start. Through toubleshooting and with your help, we determined that the injectors are not pulsing. The car will start, but as I stated before, only with carb cleaner or starter fluid, but will not stay started at all. We purchased another used computer; we have plugged, unplugged, and checked every ground wire there is. We have changed the distributor and located the crank sensor. We think that the crank sensor is good, but are not sure. Thank you very much for the help.[/Quote:0781e40c60]

Do you have a reference voltage on the CPS, try cranking the engine and backprobe the signal wire are you gettin anything.

Checking CPS resistances:

Auto-166-204 ohms @ 77degs F
Manual-423-528 ohms @ " "

Check it and comeback

About the injectors maybe shot -never know. Are you getting fuel all the way to the rail or TBI unit.

Okay why don't you get a noid light and test the injector connectors.

The cam and crank sensors tells the computer the firing order position/the speed and position of the crankhaft-now the computer has to get an ignition signal in order for it to energize the injectors thru the quad driver. Could be when the ECM don't get the ignition signal equals to no injection for the purpose of the unburned fuel collecting in the exhaust to ruin the converter.[/Quote:0781e40c60]

The CPS resistance, if we are testing it right, is at 531. It is a manual transmission. We are not sure what you are referring to when you say "backprobe the signal wire". We are getting fuel all the way to the rail. We have checked all of the fuel injectors. The power side is fine; but the pulse side nothing. Would it have something to do with the ignition relay? We don't know what the quad driver is. Is it something that we can check? Thanks again for all the help.[/Quote:0781e40c60]

The quad driver is in the computer
How about the 5volts on the CPS wire do you have it?

At the CPS the black wire should have the 5volts when key is On. White is the signal back to the computer. To confrim it -disconnect the coolant temp. Sensor-check voltage at black wire on it do you have it.

Check injectors resistances should be 10-14ohms.

Now final approach on the wiring:

Turn ignition off-disconnect the ECM harness connector. Check continuity between ECM harness connector terminal No.102 Red/Black wire to injector harness wire, No.104 Green/Black wire to injector wire, No.107 yellow/blk, No.109 blue/Blk-

102/104/107/109 are all the pulsing wire going to the injector which is the grounding wire the ECM uses to pulse the Injs.

If no continuity repair or replace harness or connector- Continuity all there-we stop on the Injectors. The injectors okay were right back to ECM terminal/ harness/connectors for damage/corrosion.

Good Luck Gentlemen
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Monday, August 27th, 2007 AT 1:09 AM
Tiny
CMCLEES
  • MEMBER
We just tried this. 106 has ground; so far we have checked everything. We have checked the crank sensor which we found at the top of the bell housing; the cam sensor, from what we understand, is in the distributor. We have switched out the distributor (with another used distributor). Is there a way to test the crank sensor?[/Quote:40a2a14182]

Crank the engine over is the injectors clicking? Better comeback am fixing to go

BTW are you getting spark and correct fuel pressure.[/Quote:40a2a14182]

The injectors are not clicking.

My son ran the car out of oil. The motor locked up. We had bought a used motor when we bought the car. We changed motors; plugged everything in; etc. The car would not start. Through toubleshooting and with your help, we determined that the injectors are not pulsing. The car will start, but as I stated before, only with carb cleaner or starter fluid, but will not stay started at all. We purchased another used computer; we have plugged, unplugged, and checked every ground wire there is. We have changed the distributor and located the crank sensor. We think that the crank sensor is good, but are not sure. Thank you very much for the help.[/Quote:40a2a14182]

Do you have a reference voltage on the CPS, try cranking the engine and backprobe the signal wire are you gettin anything.

Checking CPS resistances:

Auto-166-204 ohms @ 77degs F
Manual-423-528 ohms @ " "

Check it and comeback

About the injectors maybe shot -never know. Are you getting fuel all the way to the rail or TBI unit.

Okay why don't you get a noid light and test the injector connectors.

The cam and crank sensors tells the computer the firing order position/the speed and position of the crankhaft-now the computer has to get an ignition signal in order for it to energize the injectors thru the quad driver. Could be when the ECM don't get the ignition signal equals to no injection for the purpose of the unburned fuel collecting in the exhaust to ruin the converter.[/Quote:40a2a14182]

The CPS resistance, if we are testing it right, is at 531. It is a manual transmission. We are not sure what you are referring to when you say "backprobe the signal wire". We are getting fuel all the way to the rail. We have checked all of the fuel injectors. The power side is fine; but the pulse side nothing. Would it have something to do with the ignition relay? We don't know what the quad driver is. Is it something that we can check? Thanks again for all the help.[/Quote:40a2a14182]

The quad driver is in the computer
How about the 5volts on the CPS wire do you have it?

At the CPS the black wire should have the 5volts when key is On. White is the signal back to the computer. To confrim it -disconnect the coolant temp. Sensor-check voltage at black wire on it do you have it.

Check injectors resistances should be 10-14ohms.

Now final approach on the wiring:

Turn ignition off-disconnect the ECM harness connector. Check continuity between ECM harness connector terminal No.102 Red/Black wire to injector harness wire, No.104 Green/Black wire to injector wire, No.107 yellow/blk, No.109 blue/Blk-

102/104/107/109 are all the pulsing wire going to the injector which is the grounding wire the ECM uses to pulse the Injs.

If no continuity repair or replace harness or connector- Continuity all there-we stop on the Injectors. The injectors okay were right back to ECM terminal/ harness/connectors for damage/corrosion.

Good Luck Gentlemen[/quote:40a2a14182]

We do not have the 5 volts on the cps wire. There is also no voltage on the black wire on the coolant temp sensor.

We have continuity on the 102/104/107/109 wires.

Thanks again.
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Monday, August 27th, 2007 AT 4:45 PM
Tiny
RASMATAZ
  • MEMBER
We just tried this. 106 has ground; so far we have checked everything. We have checked the crank sensor which we found at the top of the bell housing; the cam sensor, from what we understand, is in the distributor. We have switched out the distributor (with another used distributor). Is there a way to test the crank sensor?[/Quote:5fd3f45c9d]

Crank the engine over is the injectors clicking? Better comeback am fixing to go

BTW are you getting spark and correct fuel pressure.[/Quote:5fd3f45c9d]

The injectors are not clicking.

My son ran the car out of oil. The motor locked up. We had bought a used motor when we bought the car. We changed motors; plugged everything in; etc. The car would not start. Through toubleshooting and with your help, we determined that the injectors are not pulsing. The car will start, but as I stated before, only with carb cleaner or starter fluid, but will not stay started at all. We purchased another used computer; we have plugged, unplugged, and checked every ground wire there is. We have changed the distributor and located the crank sensor. We think that the crank sensor is good, but are not sure. Thank you very much for the help.[/Quote:5fd3f45c9d]

Do you have a reference voltage on the CPS, try cranking the engine and backprobe the signal wire are you gettin anything.

Checking CPS resistances:

Auto-166-204 ohms @ 77degs F
Manual-423-528 ohms @ " "

Check it and comeback

About the injectors maybe shot -never know. Are you getting fuel all the way to the rail or TBI unit.

Okay why don't you get a noid light and test the injector connectors.

The cam and crank sensors tells the computer the firing order position/the speed and position of the crankhaft-now the computer has to get an ignition signal in order for it to energize the injectors thru the quad driver. Could be when the ECM don't get the ignition signal equals to no injection for the purpose of the unburned fuel collecting in the exhaust to ruin the converter.[/Quote:5fd3f45c9d]

The CPS resistance, if we are testing it right, is at 531. It is a manual transmission. We are not sure what you are referring to when you say "backprobe the signal wire". We are getting fuel all the way to the rail. We have checked all of the fuel injectors. The power side is fine; but the pulse side nothing. Would it have something to do with the ignition relay? We don't know what the quad driver is. Is it something that we can check? Thanks again for all the help.[/Quote:5fd3f45c9d]

The quad driver is in the computer
How about the 5volts on the CPS wire do you have it?

At the CPS the black wire should have the 5volts when key is On. White is the signal back to the computer. To confrim it -disconnect the coolant temp. Sensor-check voltage at black wire on it do you have it.

Check injectors resistances should be 10-14ohms.

Now final approach on the wiring:

Turn ignition off-disconnect the ECM harness connector. Check continuity between ECM harness connector terminal No.102 Red/Black wire to injector harness wire, No.104 Green/Black wire to injector wire, No.107 yellow/blk, No.109 blue/Blk-

102/104/107/109 are all the pulsing wire going to the injector which is the grounding wire the ECM uses to pulse the Injs.

If no continuity repair or replace harness or connector- Continuity all there-we stop on the Injectors. The injectors okay were right back to ECM terminal/ harness/connectors for damage/corrosion.

Good Luck Gentlemen[/quote:5fd3f45c9d]

We do not have the 5 volts on the cps wire. There is also no voltage on the black wire on the coolant temp sensor.

We have continuity on the 102/104/107/109 wires.

Thanks again.[/Quote:5fd3f45c9d]

How about the white wire at CPS and brown/yellow at CTS?

At pin 50 check for continuity on the black to the black wire at CPS
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Monday, August 27th, 2007 AT 5:20 PM
Tiny
RASMATAZ
  • MEMBER
Also turn key to On, do you have power at the distributor connector on the white and red wire.

This wire powers the camshaft sensor. Some EFI the computer has to see the cam signal before it activates the injectors.
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Monday, August 27th, 2007 AT 6:19 PM
Tiny
CMCLEES
  • MEMBER
We just tried this. 106 has ground; so far we have checked everything. We have checked the crank sensor which we found at the top of the bell housing; the cam sensor, from what we understand, is in the distributor. We have switched out the distributor (with another used distributor). Is there a way to test the crank sensor?[/Quote:3e2c143e2b]

Crank the engine over is the injectors clicking? Better comeback am fixing to go

BTW are you getting spark and correct fuel pressure.[/Quote:3e2c143e2b]

The injectors are not clicking.

My son ran the car out of oil. The motor locked up. We had bought a used motor when we bought the car. We changed motors; plugged everything in; etc. The car would not start. Through toubleshooting and with your help, we determined that the injectors are not pulsing. The car will start, but as I stated before, only with carb cleaner or starter fluid, but will not stay started at all. We purchased another used computer; we have plugged, unplugged, and checked every ground wire there is. We have changed the distributor and located the crank sensor. We think that the crank sensor is good, but are not sure. Thank you very much for the help.[/Quote:3e2c143e2b]

Do you have a reference voltage on the CPS, try cranking the engine and backprobe the signal wire are you gettin anything.

Checking CPS resistances:

Auto-166-204 ohms @ 77degs F
Manual-423-528 ohms @ " "

Check it and comeback

About the injectors maybe shot -never know. Are you getting fuel all the way to the rail or TBI unit.

Okay why don't you get a noid light and test the injector connectors.

The cam and crank sensors tells the computer the firing order position/the speed and position of the crankhaft-now the computer has to get an ignition signal in order for it to energize the injectors thru the quad driver. Could be when the ECM don't get the ignition signal equals to no injection for the purpose of the unburned fuel collecting in the exhaust to ruin the converter.[/Quote:3e2c143e2b]

The CPS resistance, if we are testing it right, is at 531. It is a manual transmission. We are not sure what you are referring to when you say "backprobe the signal wire". We are getting fuel all the way to the rail. We have checked all of the fuel injectors. The power side is fine; but the pulse side nothing. Would it have something to do with the ignition relay? We don't know what the quad driver is. Is it something that we can check? Thanks again for all the help.[/Quote:3e2c143e2b]

The quad driver is in the computer
How about the 5volts on the CPS wire do you have it?

At the CPS the black wire should have the 5volts when key is On. White is the signal back to the computer. To confrim it -disconnect the coolant temp. Sensor-check voltage at black wire on it do you have it.

Check injectors resistances should be 10-14ohms.

Now final approach on the wiring:

Turn ignition off-disconnect the ECM harness connector. Check continuity between ECM harness connector terminal No.102 Red/Black wire to injector harness wire, No.104 Green/Black wire to injector wire, No.107 yellow/blk, No.109 blue/Blk-

102/104/107/109 are all the pulsing wire going to the injector which is the grounding wire the ECM uses to pulse the Injs.

If no continuity repair or replace harness or connector- Continuity all there-we stop on the Injectors. The injectors okay were right back to ECM terminal/ harness/connectors for damage/corrosion.

Good Luck Gentlemen[/quote:3e2c143e2b]

We do not have the 5 volts on the cps wire. There is also no voltage on the black wire on the coolant temp sensor.

We have continuity on the 102/104/107/109 wires.

Thanks again.[/Quote:3e2c143e2b]

How about the white wire at CPS and brown/yellow at CTS?

At pin 50 check for continuity on the black to the black wire at CPS[/quote:3e2c143e2b]

There is no voltage on the white wire at CPS; we are not sure what the CTS is; we do have continuity at pin 50 to the black wire.
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Monday, August 27th, 2007 AT 7:11 PM
Tiny
CMCLEES
  • MEMBER
We just tried this. 106 has ground; so far we have checked everything. We have checked the crank sensor which we found at the top of the bell housing; the cam sensor, from what we understand, is in the distributor. We have switched out the distributor (with another used distributor). Is there a way to test the crank sensor?[/Quote:40fd3315aa]

Crank the engine over is the injectors clicking? Better comeback am fixing to go

BTW are you getting spark and correct fuel pressure.[/Quote:40fd3315aa]

The injectors are not clicking.

My son ran the car out of oil. The motor locked up. We had bought a used motor when we bought the car. We changed motors; plugged everything in; etc. The car would not start. Through toubleshooting and with your help, we determined that the injectors are not pulsing. The car will start, but as I stated before, only with carb cleaner or starter fluid, but will not stay started at all. We purchased another used computer; we have plugged, unplugged, and checked every ground wire there is. We have changed the distributor and located the crank sensor. We think that the crank sensor is good, but are not sure. Thank you very much for the help.[/Quote:40fd3315aa]

Do you have a reference voltage on the CPS, try cranking the engine and backprobe the signal wire are you gettin anything.

Checking CPS resistances:

Auto-166-204 ohms @ 77degs F
Manual-423-528 ohms @ " "

Check it and comeback

About the injectors maybe shot -never know. Are you getting fuel all the way to the rail or TBI unit.

Okay why don't you get a noid light and test the injector connectors.

The cam and crank sensors tells the computer the firing order position/the speed and position of the crankhaft-now the computer has to get an ignition signal in order for it to energize the injectors thru the quad driver. Could be when the ECM don't get the ignition signal equals to no injection for the purpose of the unburned fuel collecting in the exhaust to ruin the converter.[/Quote:40fd3315aa]

The CPS resistance, if we are testing it right, is at 531. It is a manual transmission. We are not sure what you are referring to when you say "backprobe the signal wire". We are getting fuel all the way to the rail. We have checked all of the fuel injectors. The power side is fine; but the pulse side nothing. Would it have something to do with the ignition relay? We don't know what the quad driver is. Is it something that we can check? Thanks again for all the help.[/Quote:40fd3315aa]

The quad driver is in the computer
How about the 5volts on the CPS wire do you have it?

At the CPS the black wire should have the 5volts when key is On. White is the signal back to the computer. To confrim it -disconnect the coolant temp. Sensor-check voltage at black wire on it do you have it.

Check injectors resistances should be 10-14ohms.

Now final approach on the wiring:

Turn ignition off-disconnect the ECM harness connector. Check continuity between ECM harness connector terminal No.102 Red/Black wire to injector harness wire, No.104 Green/Black wire to injector wire, No.107 yellow/blk, No.109 blue/Blk-

102/104/107/109 are all the pulsing wire going to the injector which is the grounding wire the ECM uses to pulse the Injs.

If no continuity repair or replace harness or connector- Continuity all there-we stop on the Injectors. The injectors okay were right back to ECM terminal/ harness/connectors for damage/corrosion.

Good Luck Gentlemen[/quote:40fd3315aa]

We do not have the 5 volts on the cps wire. There is also no voltage on the black wire on the coolant temp sensor.

We have continuity on the 102/104/107/109 wires.

Thanks again.[/Quote:40fd3315aa]

How about the white wire at CPS and brown/yellow at CTS?

At pin 50 check for continuity on the black to the black wire at CPS[/quote:40fd3315aa]

There is no voltage on the white wire at CPS; we are not sure what the CTS is; we do have continuity at pin 50 to the black wire.[/Quote:40fd3315aa] If the CTS is the Cam Timing Sensor, there is no brown/yellow wires; there is a six wire plug and a two wire plug going to the distributor.
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Monday, August 27th, 2007 AT 7:13 PM
Tiny
RASMATAZ
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We just tried this. 106 has ground; so far we have checked everything. We have checked the crank sensor which we found at the top of the bell housing; the cam sensor, from what we understand, is in the distributor. We have switched out the distributor (with another used distributor). Is there a way to test the crank sensor?[/Quote:06d568df59]

Crank the engine over is the injectors clicking? Better comeback am fixing to go

BTW are you getting spark and correct fuel pressure.[/Quote:06d568df59]

The injectors are not clicking.

My son ran the car out of oil. The motor locked up. We had bought a used motor when we bought the car. We changed motors; plugged everything in; etc. The car would not start. Through toubleshooting and with your help, we determined that the injectors are not pulsing. The car will start, but as I stated before, only with carb cleaner or starter fluid, but will not stay started at all. We purchased another used computer; we have plugged, unplugged, and checked every ground wire there is. We have changed the distributor and located the crank sensor. We think that the crank sensor is good, but are not sure. Thank you very much for the help.[/Quote:06d568df59]

Do you have a reference voltage on the CPS, try cranking the engine and backprobe the signal wire are you gettin anything.

Checking CPS resistances:

Auto-166-204 ohms @ 77degs F
Manual-423-528 ohms @ " "

Check it and comeback

About the injectors maybe shot -never know. Are you getting fuel all the way to the rail or TBI unit.

Okay why don't you get a noid light and test the injector connectors.

The cam and crank sensors tells the computer the firing order position/the speed and position of the crankhaft-now the computer has to get an ignition signal in order for it to energize the injectors thru the quad driver. Could be when the ECM don't get the ignition signal equals to no injection for the purpose of the unburned fuel collecting in the exhaust to ruin the converter.[/Quote:06d568df59]

The CPS resistance, if we are testing it right, is at 531. It is a manual transmission. We are not sure what you are referring to when you say "backprobe the signal wire". We are getting fuel all the way to the rail. We have checked all of the fuel injectors. The power side is fine; but the pulse side nothing. Would it have something to do with the ignition relay? We don't know what the quad driver is. Is it something that we can check? Thanks again for all the help.[/Quote:06d568df59]

The quad driver is in the computer
How about the 5volts on the CPS wire do you have it?

At the CPS the black wire should have the 5volts when key is On. White is the signal back to the computer. To confrim it -disconnect the coolant temp. Sensor-check voltage at black wire on it do you have it.

Check injectors resistances should be 10-14ohms.

Now final approach on the wiring:

Turn ignition off-disconnect the ECM harness connector. Check continuity between ECM harness connector terminal No.102 Red/Black wire to injector harness wire, No.104 Green/Black wire to injector wire, No.107 yellow/blk, No.109 blue/Blk-

102/104/107/109 are all the pulsing wire going to the injector which is the grounding wire the ECM uses to pulse the Injs.

If no continuity repair or replace harness or connector- Continuity all there-we stop on the Injectors. The injectors okay were right back to ECM terminal/ harness/connectors for damage/corrosion.

Good Luck Gentlemen[/quote:06d568df59]

We do not have the 5 volts on the cps wire. There is also no voltage on the black wire on the coolant temp sensor.

We have continuity on the 102/104/107/109 wires.

Thanks again.[/Quote:06d568df59]

How about the white wire at CPS and brown/yellow at CTS?

At pin 50 check for continuity on the black to the black wire at CPS[/quote:06d568df59]

There is no voltage on the white wire at CPS; we are not sure what the CTS is; we do have continuity at pin 50 to the black wire.[/Quote:06d568df59] If the CTS is the Cam Timing Sensor, there is no brown/yellow wires; there is a six wire plug and a two wire plug going to the distributor.[/Quote:06d568df59]

Are you turning On the key when checking the black wire

CTS=Coolant temperature sensor has a black and the brown/yellow

The black wire also goes to TPS throttle position/Crank pos. /IAT=intake air temperature sensor/EGR temp. Sensor. Check cont. On all this sensors to pin out 50

Turn key On look for power at pin 50, do you have it?
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Monday, August 27th, 2007 AT 11:06 PM

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