HELP 1990 C4 system warning
Thread Starter
5th Gear
Joined: Aug 2020
Posts: 5
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HELP 1990 C4 system warning
Hi, I have a 1990 C4 Corvette and am experiencing some trouble with it. For the past month on the automated speedo a warning pops up where the mpg usually is. The warning will flash periodically for a while with the writing "sys" and then the mpg will return. It did this randomly for a month with the car running perfectly fine through it so I just assumed it was an electrical problem with the dashboard. Today though I took it for a drive with my son and when I pulled out of a parking lot and accelerated quickly the car lurched a few times and came back to life. This happened in all of the gears. It would happen for a brief moment and then stop for a while and then come back whenever the system warning started flashing. It seems like the car isn't getting enough fuel so my son and I believe it is fuel injectors due to them being old and one of them having a damaged wire. Is it fuel injectors or something completely else? Also, is it is fuel injectors what brand should I buy? I was looking at a set of Bosch's that were set to 349 I think but I don't know if those are ok for stock. If you have any idea of whats going on please let me know it would be much appreciated. Thanks
Drifting
Joined: Feb 2017
Posts: 1,274
Likes: 399
From: Tacoma WA
2024 C4 of the Year Finalist - Unmodified
First you need to pull the codes from the system before you start throwing parts at it. Search this forum and you will see how to perform this function. There are members who are a lot more savvy than I am who can provide a link to the testing procedures. Once you have that accomplished you can start correcting what is wrong.
If it turns out to be an issue with the injectors, Fuel Injector Connection is the place to go. Call Jon and he will steer you to the right replacements if they are needed.
Do not just throw money down the rabbit hole hoping that “this will fix it”. It is all about the correct diagnosis of the problem that keeps our C4s from becoming a money pit.
If it turns out to be an issue with the injectors, Fuel Injector Connection is the place to go. Call Jon and he will steer you to the right replacements if they are needed.
Do not just throw money down the rabbit hole hoping that “this will fix it”. It is all about the correct diagnosis of the problem that keeps our C4s from becoming a money pit.
Melting Slicks
Joined: Jan 2014
Posts: 2,185
Likes: 381
From: Lunenburg MA
Thread Starter
5th Gear
Joined: Aug 2020
Posts: 5
Likes: 0
Ok, I will do some research into pulling out some codes. I took it for a drive again today to see if the problem was persisting and it has vanished. All I did was fill the gas tank up so maybe it was just running on some shotty fuel. Still going to do some research into the "system warning" thing though. Also no the other lights do not turn on at the same time. The A/C currently doesn't work and the ABS needs servicing so those lights are on all the time.
Melting Slicks
Joined: Jul 1999
Posts: 3,214
Likes: 101
From: Decatur, Alabama
Ok, I will do some research into pulling out some codes. I took it for a drive again today to see if the problem was persisting and it has vanished. All I did was fill the gas tank up so maybe it was just running on some shotty fuel. Still going to do some research into the "system warning" thing though. Also no the other lights do not turn on at the same time. The A/C currently doesn't work and the ABS needs servicing so those lights are on all the time.
