intermitent spark problem

[Cward]

Okay peoples, my buddy and I were trying to get my $350 atx to run yesterday. We were told it had a no spark problem. Well after discovering that the starter solenoid was unhooked we began looking into it. Okay supposedly previous owners replaced the computer in it. Looks like they did as the cover for it under the hood is all jacked up. They also must have been playing with the coil pack as well as the cover was just hanging off it. We verified that everything was plugged in and turned her over. Everything sounds okay. Did a cold compression test just to be sure 170-185 PSI, not too shabby for a car with 195K on it. Did discover however that the plug well seals are leaking pretty bad.Cleaned the plugs up good and turned her over again. She fired like two times. Hmmmmm. Pulled a plug and hook a spark tester to the wire. Crank for about 10-15 seconds the plug sparks twice. WTF It should definatly spark more often then that. Just for giggles we put on a known good DIS and IRCM. Still the same thing. What do you guys think? Could the coil pack be toast? Or could the crank sensor be bad. Really hoping it's not the crank sensor.LOL
Oh, I ran the codes and got 2- 539 and 111. Power to ECM pin 10?? and a all clear.
Any suggestions greatly apreciated.

 

[qiksho]

Check fuel pressure??

Check Timing??

Edit: Scratch the timing if you have 185-190 per cylinder you should be in time.

 

[SHOtimer]

I would second the above, is the fuel pump priming/running? Do you have fuel pressure?

I would also verify that all of the plug wires are routed correctly.

Doug

 

[Cward]

yep, you can hear the pump prime. So it's working. I don't think the plug wires have been played with. Geez I really need to buy a book for my SHO's,LOL. What's this Helmes(sp) manual I keep hearing about??

 

[Cward]

Okay, now the computer hasn't been replaced. Could the computer cause intermitent spark?? Kinda stumped here. HELP!

 

[Cward]

bump! Anybody??

 

[qiksho]

A search will reveal the correct routing of the plug wires. I would check this first as stated above.

Did you verify fuel pressure? Just because you can hear the pump does not mean you have pressure at the rail. For instance a clogged fuel filter will not throw a code and still allow you to hear fuel pump.

So check the fuel pressure at the rail and plug wire routing first of all.

 

[Cward]

Yep, checked fuel pressure. You can also smell fuel after prolonged cranking. As I stated before it fired a couple of times but won't start and run.

 

[93whiteatx]

firing orders

here is the firing order on a 3.2l and i think that it is the same for 3.0l. The back left wire goes to the top right coil thingy. the back middle goes to the right middle. back right goes to bottom right. the front left goes to the bottom left. the front middle goes to the top left. the front right goes to the middle left. sorry i wouldve posted a diagram of it but don't know how to put on pics yet.

 

[Cward]

I'll check the wires on Monday. The car is sitting at a friends house. I really don't think the wires are messed up though. I don't think the car is sparking correctly. We put a spark tester in the sparkplug wire and it doesn't spark regularly. As the engine is cranking for say 20-30 seconds the wire will spark 2-3 times sometimes more. It's not consistent though. like this spark-no-spark-spark-no-no-no-spark. When it has a couple sparks in a row the engine starts to fire and the the spark stops anshe just cranks. I don't know, I'm begining to think the ecu is fried.

 

[Rockledge]

rangerj DIS System Test

rangerj has put together a nice write-up on how to test the SHO's ignition system components/circuit:

First of all a couple of precautions.

1. Always connect or disconnect connections or test leads with the ignition OFF. Before switching test functions, say from an ohms resistance test to a voltage test, disconnect the test leads.

2. Use only an LED (Light Emitting Diode) test lamp. Do not use a test probe with an incandescent bulb for testing circuits containing electronic components.

3. Use only a Digital Multi Meter (DMM) to check circuits resistance or continuity on electronic (solid state) components. Use only a high quality DMM having high input impedance (at least 10 megohm). Do NOT use an analog (swing needle) meter to check circuit resistance or continuity on electronic components.

The above sage advice, regarding testing and working on electronic components, is attributable to Steve (projectSHO89), and Paul (SHOZ123). Thanks guys.

The Test(s):

-PIP Signal to PCM. Connect a DMM or LED test light between the PIP signal wire (DB - Dark Blue) and the negative battery terminal. Then crank the engine. The test light should blink, or the DMM should read between 3 to 7 volts. If NOT, the Crank sensor, Crank sensor POWER or GROUND, or the wiring/connection is faulty. If OK, then next test.

-SPOUT to DIS module. Connect DMM or LED to SPOUT wire (Y/LG - Yellow w/Light Green stripe) and negative battery terminal, then crank engine. You should get 3 to 7 volts or the test light blinks. If NOT, the control module (PCM) or wiring/connection is faulty. If OK, next test.

-Ignition Diagnostic Monitor (IDM) signal. Connect DMM or LED test light between the IDM wire (GY/O - Gray w/Orange stripe) and negative battery terminal and crank the engine. Again 3 to 7 volts or the LED light blinks. If NOT, DIS module or DIS wiring/connection is faulty. If OK, next test.

-CID Signal to PCM. Connect LED test light between CID signal wire (DG - Dark Green) and negative battery terminal and crank engine. The test light should blink. If not, CID sensor or wiring/connection is faulty. If OK, next test.

-COIL PWR (VBAT). Connect LED test light between VBAT wire (R/LG - Red w/Light Green stripe) and negative battery terminal and put the key on. The light should be ON and bright or DMM should show 12V. If NOT, VBAT wiring/connection is faulty.

-DIS electrical tests concluded. Hope this helps, rangerj

 

[Cward]

Okay, where can I get a diagram of where all these wires are??LOL

 

[Rockledge]

 

[Cward]

Thanks Rockledge, I know where everything is underhood with the exception of the control module.

 

[Rockledge]

The control module = the PCM, located up on the firewall, passenger side.

 

[Cward]

Duh, I feel sheepish.