Mechanics

94 NO SPARK OR FUEL PUMP POWER

1994 Chevrolet Cavalier • 150,000 miles

94 cavalier 2.2 It cranks but will not fire. I first checked for spark there is none. Then I also noticed the fuel pump is not coming on with key in run position.

I am ready to start troubleshooting, Possibly the ignition wire?
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J.stieg
August 11, 2012.



Check and test the crankshaft position sensor and also the fuel pump relay-start here-check engine light is it coming on prior to the problem? also go to this link: http://www.2carpros.com/articles/car-cranks-but-wont-start


Rasmataz
Aug 11, 2012.
Ok, can you get a diagram for the crank sensor. Would that keep the fuel pump relay from coming on even before cranking?


Tiny
J.stieg
Aug 11, 2012.
Check the ECM fuse if its okay-if so check the fuel pump relay ground point G110 and fuel pump control circuit on the computer to include the fuel pump ground below left front seat

CPS at right rear of engine


Rasmataz
Aug 11, 2012.
Wire colors do not seem to be the same as the diagram for me to test CKS.

I did some checks and coil doesn't seem to be getting any ground pulse, But there was + power, and fuel injectors are not opening both legs seem to be positive.

Yesterday the fuel pump was stuck on with key in run position, but today fuel pump wont come on in run position.

Bad ECU or crankshaft sensor?


Tiny
J.stieg
Aug 14, 2012.
I could have been looking at the VSS, I will look again.


Tiny
J.stieg
Aug 14, 2012.
Should there be 5v at REF, there isnt.


Tiny
J.stieg
Aug 14, 2012.
Recheck below: Check the ECM fuse if its okay-if so check the fuel pump relay ground point G110 and fuel pump control circuit on the computer to include the fuel pump ground below left front seat

CPS at right rear of engine
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Rasmataz
Aug 14, 2012.
I checked G110 where ground enters the ECU at A1 and C13 and it had good cotinuety.

ECM fuse is is good but I need to check where it comes into the ECU. Same thing for the F/P ground.

Can you get a full diagram of the ECU please?


Tiny
J.stieg
Aug 14, 2012.
Direct power to the FP from the battery and see if it'll come on


Rasmataz
Aug 14, 2012.
Yes, I checked that first, fuel pump comes on fine being jumped.
The ECU is not throwing F/P relay for some reason.

Summery: 1. ECU is not letting F/P come on.
2. Ecu is not ground pulsing to coil(no spark)
3. Fuel injectors are not firing.
In run or cranking.


Tiny
J.stieg
Aug 14, 2012.
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