94 Z28 randomly cuts out
06-07-2009, 07:26 PM
#1
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94 Z28 randomly cuts out Ok, so lately I've had some issues with my 94 Z28. Last week it stalled on me twice in a row at two stop lights. Just shut off as I was sitting there. Took me a good 5 minutes each time until I got it started. Then it ran like normal. Took it to the shop hoping it was a fuel system problem, had them check/clean the fuel system. Got it back, seemed ok ( it was even running a little better), then today ( 4 days later) I'm pulling out of a light going slow, and it cuts out again as I'm going along. Just shuts off. This time, it started right back up though. I've also noticed that once it is warmed up, the idle isn't quite smooth. I can feel small vibrations as it idles, it'll be smooth and the have a small barely noticeable hiccup and a slight vibration. Does this sound like the opti to anyone? Anything else it could be?
06-10-2009, 01:09 AM
#2
Spark Issue I just got done fixing similar issue on my car twice within a year.
It could be a bad opti but most likely its a bad Ignition control module(ICM).
The reason they go bad is because they get heat soaked, because they are sitting on top of the head basically.
You can get it tested at autozone for free and go from there.
If it fails the test, make sure you get the AcDelco brand, others crap out quick.
Someone else can chime in about trouble shooting opti.
It could be a bad opti but most likely its a bad Ignition control module(ICM).
The reason they go bad is because they get heat soaked, because they are sitting on top of the head basically.
You can get it tested at autozone for free and go from there.
If it fails the test, make sure you get the AcDelco brand, others crap out quick.
Someone else can chime in about trouble shooting opti.
06-10-2009, 01:54 PM
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That does sound like it would make sense, as most of the problems have happened during hot weather in stop and go traffic when it gets hot ( I live in downtown Pittsburgh). Would that cause it to not start back up after shutting it off after in traffic? I also haven't gotten any lights to show up, and the engine has this nasty vibration at idle ( it has these quick jolts, when you pop the hood you can see the thing shaking).
06-10-2009, 03:31 PM
#4
yea that sounds exactly like what my car was doing. It stalls, takes time to turn back on and will drive fine until next time it stalls. Eventually it will get to a point when the car starts and turns off immediately and then doesn't start.
Its a spark issue, you already had fuel checked out.
Its a spark issue, you already had fuel checked out.
06-10-2009, 07:43 PM
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**update** Well, very odd turn of events.. had it at the mechanics, and he didn't have a problem with it...until I came to pick it up. It wouldn't start, upon looking at it, it is getting spark...but the fuel injectors weren't firing 
. Both of us were oddly perplexed. Still need to check if it's throwing any codes, that particular mechanic doesn't have the equipment on hand for that particular year. So what was one problem, seems to be escalating :/
. Both of us were oddly perplexed. Still need to check if it's throwing any codes, that particular mechanic doesn't have the equipment on hand for that particular year. So what was one problem, seems to be escalating :/
06-11-2009, 08:20 AM
#6
I had a simular problem, turned out to be the POSITIVE terminal Accessory post, not the battery.
On the LS1 compartment its on the Drivers side, I think that post is on the Passangers side on the LT1, like yours.
Anyway, that nut on th epost wiggled lose on me causing the wires to heat up and burn/melt down, the car would shut down...sometimes for seconds other times for minutes.
Worth a check!
On the LS1 compartment its on the Drivers side, I think that post is on the Passangers side on the LT1, like yours.
Anyway, that nut on th epost wiggled lose on me causing the wires to heat up and burn/melt down, the car would shut down...sometimes for seconds other times for minutes.
Worth a check!
06-12-2009, 12:21 AM
#7
**update** Well, very odd turn of events.. had it at the mechanics, and he didn't have a problem with it...until I came to pick it up. It wouldn't start, upon looking at it, it is getting spark...but the fuel injectors weren't firing . Both of us were oddly perplexed. Still need to check if it's throwing any codes, that particular mechanic doesn't have the equipment on hand for that particular year. So what was one problem, seems to be escalating :/
. Both of us were oddly perplexed. Still need to check if it's throwing any codes, that particular mechanic doesn't have the equipment on hand for that particular year. So what was one problem, seems to be escalating :/Did your mechanic check the ICM and how did he reach at conclusion that injectors aren't firing?
