Well, I just finished the task of replacing my Opti for the first time. It's really damn cold outside, and I'm freezing. But, the car still won't start. It cranks, but doesn't spark. I NEEED my car back, but I can't afford to throw parts at it, hell the Opti set me back $330 already!!! It's just wierd, this problem just showed up, no symptoms. I just turned the car off after driving it one night, and it didn't start back up. I had to get AAAed home. I have checked for spark from a plug, and after that I figured I'd check from the coil and it isn't giving spark either. Is it a coil, or module? Also, my computer won't read out codes to me when I use a scan tool, the connection fails. Help is apprecaited, as I've spent quite a bit of time trying to fix it, and it still isn't running

Thanks,
Nick

 

That sucks man, Im in the same boat as you. I dont have a garage so I freeze in the winter. Have you gone over everything? Check the ignition module connections, and the opti harness.

 

I tried replacing the coil and still no success. So, has a new opti and coil now. What should I check (connections?)?

Nick

 

Don't laugh, but when I changed my Opti last year, i put a little tiny black "O" ring in the wrong place, and the car wouldn't start........i didn't pay attention when i took the old one off, and the whole time i spent putting EVERYTHING back together, i was wondering about if i put that damn O ring in the right spot......it sucked. The car tried to crank, but nothing, so i took it ALL back apart and put the O ring in the right spot and it started right up.

What exactly does your car do when you turn it over? Does it atleast "try" to crank? Is it getting fuel?

Another weird thing that happened to me once (i have a 94 Z28 by the way), is i was driving and my engine cut OFF, but my battery was still going strong.......i was scratching my head. I ended up checking my ignition fuse, and it was blown.....after some troubleshooting, i found that i had shorted out the ignition wire going to the brake switch (something like that) that is underneath the carpet to the left of the brake pedal. Evidentally, i smashed the wire into the medal by all of the thousand of times that i would stretch out my leg. So, a splice and an environmental sleeve fixed that right up!

Hope this helps!

 

sorry to hear- about to do the same thing to mine tommorow- in a parking lot- and its supposed to be snowing-

sadly need to get car running so i can drive home to connecticut from rochester on saturday

goodluck

 

I haven't checked for fuel, because I figure without spark at all it isn't going to have a chance anyways. All the fuses checked out OK. As for cranking, it cranks like it would if it were starting. Remove the PCM Batt fuse from your car, that's how it cranks. Like there is no signal to spark. So, I guess I'll check the connection to the Opti and/or the coil? Have to do that tomorrow.

 

OMG we should get our own little forum on this board. My opti is dead too. I say we go kick some **** at the lab where this POS was designed.

 

I guess by now you ruled out spark plugs/spark plug wires/opty spark. I know because you are saying there isnt a spark arriving at the opty and you have a brand new opty spark.

I would check the electronic conection to the opty.. did you remember to plug it back in? I almost forgot my self last year.... The Coil can be tested but I am afraid if you do it wrong you may shock yourself to death... no joke. But if you momentarily apply power to the primary coil ... when you disconect the applied power it should produce a high voltage spark on the secondary. If you dont know what I am talking about... Just buy a new one. I just dont want you to injure yourself or damage any electronic parts in your car.

When you said no spark to opty I was thinking more like.... coil... ignition module....opty....PCM. The opty optical sensor is it plugged in properly? I would Try the coil and the module next.


Marvin

 

Ok, no spark still. I've replaced the Optispark and coil. I've checked for signal going to the ICM and there is none (like .1 volts AC). The harness going to the opti gets voltage (+5, +5, +12). And the signal wire of the harness checked out w/ my multimeter (isn't broken). The wire going from the PCM to the ICM checked out, and the wire from the Opti signal to the PCM checked out. I suppose the only thing left is the PCM?!

That sound like the problem then?

Nick

 

Just wondering if anyone has any more info before I buy a PCM I may or may not need. There aren't really any more ignition parts that I can replace, and all the wiring checked out :S. Is this just a freak thing, what could cause the PCM to die like this? Just looking for a second opinion before I spend some more money on this car.

Thanks,
Nick

 

Similar case different car.

I visited my mom. Parked. went inside for 2 hrs. Came back out. Car would turn but no start. Found there wasnt any spark. Problem was a bad ICM.

This was the Ignition Module on a 1979 Ford Escort GT. Happened two times. Once I was making a turn and splat! Like someone just turned the ignition Key off.

Ford is being sued because of this module.

Before you run to buy one do a search to find out if there is anyone who knows how to test them on the LT1. I dont know if you already did that. You checked all the voltages so I asummed you did but just in case.

Marvin

 

I don't mean to have to TTT this, but I don't know what to replace next to get my car running. Given what I've said, I would assume it is the PCM? But, it could also be the ICM and/or something else. Any guidance would help me immensely. I need my car back, it's really hectic not having a car!

Thanks a lot,
Nick

 

First, please elaborate how you determined there was 12volts going to the opti

Second, when you where looking for AC voltage at the ICM, did you check the white wire while it was being cranked?

Does the pink wire on the ICM and coil have 12volts? Does the ICM have a good ground on the black wire?

 

I determined it becuase the connector had it. Yes i realize that if it wasn't making the connection, then it wouldn't have it. BUT, the terminals appear to be in excellent condition w/ no corrosion, aren't pushed inside the connector, and the connector doesn't have any damage to it.

The AC Voltage at hte ICM was on the white wire while being cranked. Obviously there wouldn't be any voltage on it if the car weren't being cranked. (I'm not saying that sarcastically to **** off people, I'm just saying that i realize that)

The ICM and coil are both receiving 12 volts and good ground.

 

My bad. I had a brain fart. At first didn't see where 12 volts was going to the opti. Not questioning the method.

You have to be sure the low and hi res pulses are actually getting to the PCM. I assume you would get codes if they weren't. If I were you, I would look for changing level on the 2 lines at the PCM while you rotate the crank by hand. If you have those 2 signals changing at the PCM but have no IC signal. I would think the PCM has a problem. Before you go buying one, try a donor.