Yesm, sometimes ignition modules will die slow like that. Before spending money...Check the fusable link wire on the starter solinoid, see if it's loose. If you have an ohm meter, check your coil wire. If no meter, at night (really dark) with the engine running, see if the wire/s arc inside, kind of a glow looking zap. That is if you don't have wires that are suppose to do this....It's an old trick, you can see the carbon arc inside the wires when they start getting bad. If it's an HEI distributor, maybe it's time to rebuild the cap. Take the coil off & look for carbon tracking. Sometimes they'll arc through the rotor to the distributor shaft. No spark gets to the rotor. Seen this happen a few times on my own stuff. Look at the inside center of the rotor, should be clean. If it's got carbon arcing, there's yer trouble. Stranger things have happened.....

 

i have that problem too on my 2.5

 

Going by your sig (LT1) I'd say your opti is soaked. You could try drying it out and it may work. Your best bet would be to replace it and use some RTV to make sure the new one is totally sealed up.

 

actually, i thought it was the opti myself, because when i tested for spark (arcing it off metal at each of the cylinders i got nothing), i replaced it, then i went to start it and nothing, so i pulled the wire going from the coil to the distrubitor and it did nothing at first but then i got spark from that

the starter is fine, when i get spark it turns right over, thats why im thinking its the module, but im not even sure how the ignition module works.....all i know is that it gives me spark sometimes, and not others, the coil and coil wire have been tested and are good.

edit: when i had orginally tested it, i tested the wire at the coil and it had spark, then i put it back on and tested at a cylinder, and had none...thats why i replaced the distributor (entire optispark unit) i would think it would have to be the control module seeing how i can arc some spark out of the coil once, turn it off try again and have nothing.

 

Remove the Ing Module and take it to AUTOZONE and they will test it for FREE Make sure they test it about 10 times in a row to get the module good and hot.

 

i actually did take it to my local autozone....at first the guy was like i cant test it, we've had too many problems with the tester and have gotten screwed over on it, and until we get a new tester we aren't going to use it, i then pursuaded him into testing it, he looked up the part number in his book and it wasn't even there!

so even if he did hook it up, he would have no data to go off of.

 

i think i solved your problem, put a forsale sign on it

 

easy $60 dollar fix, i could dig myself into a 5 year debt plan maybe?

 

at that rate, yes, you owe larry millions! Alright fix it then

 

Evan,

check out shoebox's site, he has a icm troubleshooting link. this goes along w/ the maf problem.. could be a bad ground or something.

good luck.

 

at that rate, yes, you owe larry millions! Alright fix it then

hahah no you knucklehead, thats where all my money has been going, i have no new debt, i was reffering to your outstanding 5 year plan to pay off your truck!

everything i have gotten is paid for, i just cant keep up with car insurance!!

jeff - i cleaned the maf with some carb cleaner and the code went away, ive tested every ground i can find, they all look pretty solid.

 

hahah no you knucklehead, thats where all my money has been going, i have no new debt, i was reffering to your outstanding 5 year plan to pay off your truck!

everything i have gotten is paid for, i just cant keep up with car insurance!!

jeff - i cleaned the maf with some carb cleaner and the code went away, ive tested every ground i can find, they all look pretty solid.

well yeah, i got $7000 more to pay but i like mods so i buy those, if i didn't then it'd be atleast 5 or 6000. not bad though?

 

maybe put a test light on the coil + wire and fire the truck, watch to make sure you have power the whole time your cranking, could be a faulty ignition switch or wire?

got to eliminate all the maybes and could bes man. don't know what else to tell ya. are you watching it fire up w/ datamaster to make sure you aren't missing anything? searched z28 forum?

good luck

 

what role does the pcm play in this? im not throwing any codes right now, but is it possible that the pcm just went bad?

the ignition system should be sound at this point...i have relatively new plugs and wires, and brand new optispark unit, coil is good, icm is good.....power is getting to the icm and coil, the grounds were good, im getting all the different voltage readings across the 4 wires on the distruibtor.

this problem is really stumping me, it started up a couple of times in between all the times it hasn't....thats gotta tell me something, im just not sure what.

 

have you checked fuel pressure, voltage and grounds at the pcm? the one ground that's bolted to the block down by the oil dipstick tube?

when it fires, does it run fine, skip miss, hesitate or anything? are you sure you got all the wires tight on the opti, i know that's a beyotch, made sure you aren't crossing any wires. have you got the service manual, checked the diagnostic flow chart?

the only thing i can think of is the ecm messing up, opti not sending high res signal or possible power/wire connections.

I've got a spare ecm sitting in my garage that i can send you, if you'd throw a stock program back in for me, right now it's got my lt4 burn in there. I sold all my cables and programming crap when i let the truck go, have a guy that wants to convert obdii to obd, needs an ecm and doesn't have any programming capabilities.