93 Z28 problem
Thread Starter
Teching In
Joined: Feb 2013
Posts: 33
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From: N. Ky
93 Z28 problem My 93 is having some issues lately. I'm not up with all the EFI stuff, but familiar enough to muddle through it. Right now, it's real hard to start, like there's no spark. It was difficult to start cold all last year. Once it was warm it had no issues. Now the thing will run for a little while, then die, and won't restart. It's like it has no spark again, just cranking over not even getting the slightest fire. Fuel pump and pressure seem good. During the no starts the pump primes everytime. I checked pressue once and it was at 45psi. Any help is greatly appreciated.
DJ
DJ
TECH Regular
Joined: Dec 2011
Posts: 461
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From: Hastings, Nebraska
Need to know more info about the car. any mods? what transmission?
service engine soon light on?
did you happen to notice if it stayed at 45 psi or if it started bleeding off after a few seconds?
otherwise check threw your ignition, ICM,
service engine soon light on?
did you happen to notice if it stayed at 45 psi or if it started bleeding off after a few seconds?
otherwise check threw your ignition, ICM,
When was the last tune up done? also simple checks would be to take icm and coil off and test them, autozone can test the icm, just ask them to test it a couple of times until its real nice and hot. Shbox's website has a guide to check the coil.
also the opti could possibly be bad, not saying it is but always a possibility
also the opti could possibly be bad, not saying it is but always a possibility
It runs then dies after the engine warms up? Sounds very common for icm / opti failure.
If you let the car sit and cool alittle bit will it start back up? Again check shbox site for diag procedures before you start throwing parts at it unless you're like me and have 2 spare icm's in the garage
If you let the car sit and cool alittle bit will it start back up? Again check shbox site for diag procedures before you start throwing parts at it unless you're like me and have 2 spare icm's in the garage
Thread Starter
Teching In
Joined: Feb 2013
Posts: 33
Likes: 0
From: N. Ky
Thanks guys. I was thinking ICM, and or opti. To answer some questions, yes the check engine light is on (been on sine I bought it). Fuel pressure stays steady. I've replaced my MSD coil after it started to leak spark to it's own outer coil plates. It seemed like it helped, started right up, but next time SOS. Stock motor, A4, only mods are nitrous wet shot, CAI, headers, Crane HI-6 ignition, CSR, and other non motor related stuff. Opti supposedly has 40K miles on it. I've replaced O2s, plug wires and plugs (last fall) and was getting ready to do a rotor and button, but was thinking about a new opti. It does seem to start up again after it cools, but before it's ever been running it's hard to start on cold starts, which makes me think it's not a heat related problem. I'll see about getting the ICM checked out this weekend.
