92 2.3 no spark after ICM replace

92Rustang2.3

New Member
Oct 21, 2010
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Car was runnung rough tested my way to a bad ICM (Ignition Control Module. I replaced the ICM. now, I have no spark at all. removed, and tested ICM,and coils,all good. please help, this is week two working on this car.
 
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When my car had those symtoms it turned out to be the Crank trigger. Its a bit of a pain to replace, but it can be done in a few hours. I would have your new ICM tested, and if its good, i would replace the crank trigger.

Dr.
 
Watch out . . .

A while back we had a Ranger with a bad ICM. Replaced it five times before I threw my hands up and had my local salvage yard find me a true Motorcraft. Even though it was used, it worked perfectly. The sad fact is, we have a huge problem with offshore parts and it's sometimes hard to tell the good from the bad. My basic tenet is, believe what you see.
 
Where is the crank trigger? Did the N/A non-turbo have one? Is it also known as the crank positioning sensor?


it's located on the front of the engine, next to the harmonic balancer. to get to it, the water pump pulley (at least loosen the bolts first before removing the belts), alternator, remove the belts, then the plastic timing belt cover. Remove the crank pulley, and the balancer. you should see it to the right of that. i think it's 2 or 3 tiny 8mm bolts to get it off. the only "fun" part is that the wiring harness goes behind the back plastic timing cover case, and without destroying one or the other (case or wiring harness) you have to remove the timing belt.

If you do, now is the time to replace the belt, if you don't want to remove the belt, you can cut the wires somewhere behind the alt and re solder them to the new one.
 
I said screw testing,and replaced both... no change. Any other idea's?


I assume you replaced the DIS and coil packs?


If so - it could be the ECM. I had my ECM go bad a few months ago - got lucky and scored one out of the JY and it was a re-furbished unit - the date on the refurbished was in 2006.

The symptoms on my bad ECU was as follows:

turn key on - hear the fuel pump run and run and run and run. Sometimes it would continuously run for 30 seconds up to 3 to 4 minutes. If I cranked the motor at any time during this process there was no fire in the motor (no spark). As soon as I heard the fuel pump kick off, turned the key and engine would fire up and run fine. This usually occured at lunch and leaving work in the evening - when the inside of the car was hot. After the initial firing of the motor i could turn it off and refire immediately.

I replace the ECM and all that went away.

the nice thing about down here - the JY sells them for 15 bucks.
but remember - you need to get one for your car auto ECM is different than a 5 speed and you need the one for your year range - 87 to 89 is interchangeable and 90 to 93 are interchangeable.
 
This is a head scratcher now.....

ok a question. did you keep the original ICM? if you did, does putting it back on give you the rough running?

next possible thing that I can think of is tht it might be fuel delivery related.....as in the actual pump in the tank, the relay module itself, fuel filter or bad pressure regulator. Unlike the 5.0 cars, the relay is part of a relay module found on the passenger side shock tower - its the big honking electronic box with alot of wires going to it. From what i understand that box also controls the fan and it isn't easy to open up to just replace the relay.

I'd start with the easy stuff first - drop the fuel filter and when you have it off, have a helper turn the iginition on for a second or two to see if you get some fuel pumping out of the line - if you don't then the next step is to determine if it's the pump or the pump relay.

Just throwing a wild guess out there.
 
No, it doesn't run at all now. Would the fuel system affect the spark? I'll pop the filter, and figure that out. I do hear the pump turn on with the key. I really appreciate your time.
 
no problem - we'll try to figure thos one out. you should be able to hear the pump run for 2-5 seconds and shut off with the turn of the key to on. like i said before, when my ECU went bad, the pump ran and ran and ran usually over 30 to 40 seconds and that shouldn't happen.

just throwing out possible other problems - if the pump doesn't supply fuel then you can get the no start symptoms - how did you determine no spark, did you pull a wire and see if it sparked?
Does the tach move while trying to start?

Also, keep in mind that even if you hear the pump there is a rubber line in the tank that connects the pump to the metal line that connects to the outside of the tank. it is possible that this hose has either slipped off or has cracked or is eroded - the ethynol in the gas does destroy old rubber lines. Lets try to eliminate possible problems - the easiest way to confirm fuel delivery is to eithre put a guage on the fuel rail - you can use an air pressure guage for a quick check - or do the fuel filter replacement - chances are the filter might need replacing anyways - and do the fuel check while the line is disconnected.