No power to the coil pack! Please help!

Tiny
SAMUEL1214
  • MEMBER
  • 1998 PLYMOUTH NEON
  • 2.0L
  • 4 CYL
  • 2WD
  • MANUAL
  • 174,000 MILES
Well I've changed the crank sensor and I replaced the crank sensor plug and wires to it. Brand new battery, coil pack, spark plugs. The relays are all good. The fuel pressure is 48lbs. Please help
Sunday, March 19th, 2017 AT 7:24 PM

12 Replies

Tiny
HMAC300
  • MECHANIC
  • 48,601 POSTS
Try a security system reset see our link and then check asd relay and fuses under hood. it may be a key/transponder problem with security a new key will not help if you have another one then it may start.
https://www.2carpros.com/articles/how-to-reset-a-security-system
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Monday, March 20th, 2017 AT 7:14 AM
Tiny
SAMUEL1214
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  • 7 POSTS
I've tried that. Their is no Check Engine Light I've ran codes on the car and nothing pops up and I've used four different scanners. Everything is getting power and working but the coil pack wires. And I don't know if this helps but there was a brown liquid in the plug that goes into the Ecm coming from the firewall
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Monday, March 20th, 2017 AT 9:29 AM
Tiny
HMAC300
  • MECHANIC
  • 48,601 POSTS
Have you checked asd relay like I said in last reply?It may be abad wire between asd relay and coil
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Monday, March 20th, 2017 AT 9:36 AM
Tiny
SAMUEL1214
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Yes the relay is good and I checked the wires to it getting power for a second then it cuts off but no signal
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Monday, March 20th, 2017 AT 9:38 AM
Tiny
HMAC300
  • MECHANIC
  • 48,601 POSTS
Try jumping the relay and see if it runs if it does it's a bad relay or the prongs aren't making good contact the only other thing I can suggest is to use a pro scanner and see if something else turns up or have mechanic figure it out
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Monday, March 20th, 2017 AT 11:58 AM
Tiny
SAMUEL1214
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  • 7 POSTS
I've used a $6000 dollar scanner and nothing happens it just said no connection.
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Monday, March 20th, 2017 AT 3:58 PM
Tiny
HMAC300
  • MECHANIC
  • 48,601 POSTS
Then if no connection you have to find out whether it's a bad connection at aldl or broken wire to see why then scan it with that scanner. I have no other thing to suggest. I'll pass this on to someone else
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Monday, March 20th, 2017 AT 4:29 PM
Tiny
SAMUEL1214
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  • 7 POSTS
Okay well I've tried everything I got little scanner for 50 bucks and it made connection with the car. And there is no security system in this car. And the relays are working like they are supposed to be
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Monday, March 20th, 2017 AT 4:36 PM
Tiny
CARADIODOC
  • MECHANIC
  • 33,752 POSTS
Hi guys. You're overlooking one important comment. You said you only have 12 volts to the ignition coil pack for one second. That is exactly how the system is supposed to work. That 12 volts should come back, via the automatic shutdown, (ASD) relay, during engine rotation, (cranking or running). That is how the system stops the fuel pump from dumping raw fuel onto the ground if a line is ruptured in a crash. The engine can't run with no fuel pressure. No signals arrive from the crankshaft position sensor or camshaft position sensor when the engine has stalled. With no signal pulses, the Engine Computer turns the ASD relay off along with the fuel pump or its separate fuel pump relay.

If there was a fault code for the crank or cam sensor, they would have been erased if the battery was disconnected. They often will not set again from just cranking the engine. They typically set when a stalled engine is coasting to a stop. In that case, if you don't have spark, you need to look on the scanner under "Inputs and Outputs", or "Sensor Data" to see if the signals are showing up for those sensors. I have a Chrysler DRB3 for all of my vehicles. That one shows each sensor as "Present" or "No" during cranking. I'm not sure how that would show up on aftermarket scanners.

The scanner will also show when the ASD relay is being commanded on. You can do the same thing by measuring the voltage on the wire that is the same color at every injector, the coil pack, or either small terminal on the back of the alternator. That is usually the dark green / orange wire. Back-probe through the rubber weather-pack seal with a test light. Digital voltmeters don't respond fast enough. You will see the light turn on for one second when you turn on the ignition switch. That is when you'll hear the fuel pump run too. What is important is if the light turns on again during engine cranking.

Do you have a single or dual-cam engine?
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Monday, March 20th, 2017 AT 5:01 PM
Tiny
SAMUEL1214
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I have a single cam
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Monday, March 20th, 2017 AT 5:04 PM
Tiny
SAMUEL1214
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And no it does not come back on while cranking
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Monday, March 20th, 2017 AT 5:08 PM
Tiny
CARADIODOC
  • MECHANIC
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Dandy. Probably the best suspect is a failed camshaft position sensor, but we never approve of throwing random parts at the problem unless the diagnosis points to them. Use your scanner to see if those signals are showing up. The next suspect is the crankshaft position sensor.

The third one is more elusive. You first have to check the timing belt to see if it has jumped. If it jumps one tooth, the Check Engine light will turn on, and the fault code will refer to "cam and crank sync". If it jumps two teeth, the Engine Computer will shut the engine down to protect the valves. If it jumps three teeth, or the timing belt breaks, the open valves will be hit and bent by the pistons as they coast to a stop.

The elusive problem is when you have the "cam and crank sync" fault code, but the timing belt is right on the money. There is a round dowel pin between the camshaft and the sprocket, to set the sprocket's position. That dowel pin can shear off and allow the sprocket to rotate slightly on the camshaft. That will make the valve timing late and look to the computer as though the belt had jumped. If the Check Engine light is ignored, the sprocket can spin just to the point of where the computer is trying to decide if it should stop the engine. The common symptom is intermittent stalling, or the engine only runs for a few seconds, then stalls, or intermittent spark from only one of the two ignition coils. People are not able to drive the car very long like that. The sprocket will continue to spin until it looks like the belt has jumped two teeth, then you'll have a crank / no-start.
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Monday, March 20th, 2017 AT 5:46 PM

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