Dies while driving
Thread Starter
Advanced
Joined: Jun 2005
Posts: 97
Likes: 2
From: Carlsbad Ca
Dies while driving
My 91 dies while driving, sometimes at idel. I can go weeks and it wont happen. Generally it starts right back up, no problem. Until today, this time I was driving, stepped on the gas and nothing. Coasted to a stop, tried to start it. It turns over fine, but it just wont start.
I dont have a code reader, and my manual is pretty crappy. Any place I should start looking before I have to tow it some place expensive?
Thanks!
Jeff
I dont have a code reader, and my manual is pretty crappy. Any place I should start looking before I have to tow it some place expensive?
Thanks!
Jeff
Le Mans Master
Joined: Feb 2006
Posts: 8,753
Likes: 9
From: Louisiana
Take the ICM out and have it tested at Autozone for free. If not that then attach a fuel pressure guage and observe fuel pressure while driving. If the fuel pressure falls when the engine dies, there is the problem. Check for spark the next time the engine dies.
Race Director
Joined: Dec 2006
Posts: 10,383
Likes: 4
I'm not an L98 guy but the things you need for engine start are of course rotation, compression, fuel/air, and spark.
This site walks you through how an L98 gets those at startup one step at a time.
http://www.corvettebuyers.com/c4vettes/l98.htm
Good luck and let us know what the fix was please!
This site walks you through how an L98 gets those at startup one step at a time.
http://www.corvettebuyers.com/c4vettes/l98.htm
Good luck and let us know what the fix was please!
Drifting
Joined: Nov 2005
Posts: 1,324
Likes: 5
From: Charlotte NC
This may or may not apply, but I'll add it to the heap...
Years ago I had a sh--box car that had the same problem. It would drive fine, then intermitently die for no reason. Sometimes it would start right away, other times not. After checking EVERYTHING related to fuel, spark, compression, etc., a stranger overheard my conversation and asked if I had checked the fuel tank for debri.
Long story with an ending, leaves were found in the tank and would get sucked up against the pickup....after cleaning the tank out, that thing drove like a fine piece of $500 machinery!
Years ago I had a sh--box car that had the same problem. It would drive fine, then intermitently die for no reason. Sometimes it would start right away, other times not. After checking EVERYTHING related to fuel, spark, compression, etc., a stranger overheard my conversation and asked if I had checked the fuel tank for debri.
Long story with an ending, leaves were found in the tank and would get sucked up against the pickup....after cleaning the tank out, that thing drove like a fine piece of $500 machinery!
Thread Starter
Advanced
Joined: Jun 2005
Posts: 97
Likes: 2
From: Carlsbad Ca
Thanks guys the more info the better. The car wont start, so checking anything while driving is out. My manual is horrible and I know nothing about Corvettes. Plenum? Manifold? Same thing?
Leaves in the tank? Not likely, how would leaves get into the tank?
Are there any sites that have better pictures and motor descriptions?
Thanks
Leaves in the tank? Not likely, how would leaves get into the tank?
Are there any sites that have better pictures and motor descriptions?
Thanks
Race Director
Joined: Dec 2006
Posts: 10,383
Likes: 4
Le Mans Master
Joined: Feb 2006
Posts: 8,753
Likes: 9
From: Louisiana
One other thing: If the Service Engine Soon light is on....check for stored codes. Since your ECM is under the hood, you may just want to check/clean the connections, and they are known to get hot and fail until they cool down also. If it is suspect, place a bag of ice, that will not leak, on the ECM and see if the dying stops. My bet is still on the ICM though.
Racer
Joined: Oct 2006
Posts: 286
Likes: 0
From: Olympia Washington 91 Z07 Coupe, 6spd, Borla Exhaust, Perf. Ignition, K&N Filter
a fuel filter can be plugged up, your coil in the distributor may be old, maybe you have a damaged plug wire, or a loose cacuume tube, just look at the basics first, and hopefully it will be something small, good luck.
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Racer
Joined: Oct 2006
Posts: 286
Likes: 0
From: Olympia Washington 91 Z07 Coupe, 6spd, Borla Exhaust, Perf. Ignition, K&N Filter
the ecm according to the chiltons book is right by the battery, on the left of it if your looking at the car from a deer perspective, just in case u want to take it to someone to get it scanned or what not
Safety Car
Joined: Jul 2004
Posts: 3,834
Likes: 30
My 91 dies while driving, sometimes at idel. I can go weeks and it wont happen. Generally it starts right back up, no problem. Until today, this time I was driving, stepped on the gas and nothing. Coasted to a stop, tried to start it. It turns over fine, but it just wont start.
I dont have a code reader, and my manual is pretty crappy. Any place I should start looking before I have to tow it some place expensive?
Thanks!
Jeff
I dont have a code reader, and my manual is pretty crappy. Any place I should start looking before I have to tow it some place expensive?
Thanks!
Jeff
Thread Starter
Advanced
Joined: Jun 2005
Posts: 97
Likes: 2
From: Carlsbad Ca
It runs again,
Thanks guys! I replaced the ICM this morning and I ran down the coast highway with the top down!
You were right its a pretty simple fix and only $54 for the part.
This forum has gotten me through a couple of jams, still learning about this car and motor.
Thanks again,
Jeff
You were right its a pretty simple fix and only $54 for the part.
This forum has gotten me through a couple of jams, still learning about this car and motor.
Thanks again,
Jeff
Advanced
Joined: Jun 2005
Posts: 60
Likes: 0
Check the butterfly in the throttle body. My 88 did the same thing and I was about to spend a bunch at the dealer to fix the problem. An old mechanic told me to check out the trottle body, sure enough it was all black and as instructed I used a tooth brush and GM throttle body cleaner. Car ran and idled like new. It has been over a year and has not stalled again.
Instructor
Joined: Jul 2006
Posts: 202
Likes: 1
From: boise id
sounds like your fuel pump needs to be replaced to me... same thing happened to me, at least its an easy fix. you dont need to drop the tank so only takes about one hour, less than a $100 dollar fix 
didnt see that the problem was solved