c4 corvette vatts system
Thread Starter
2nd Gear
Joined: Jan 2021
Posts: 2
Likes: 0
c4 corvette vatts system
So ive had my C4 corvette for 4 yrs..its a manual... So I have had issues with the vatts.. The ignition key has been changed out and there is no chip on the key. So on some days the key will turn and the car ignites.... Drive it off and park it at my parents like for two hours.. Try to start it and the car will not turn on... So, I would get out of the car and use alcohol on the key... it wouldnt turn on... would wait 4 , 6, 8 , mins doing this several times and at one point it turns on....What can I do to fix this problem?
Cruising
Joined: Aug 2019
Posts: 13
Likes: 1
From: Fly-over Country
A common fix on other GM cars of the era is to bypass it. Figure out what resistance value your key chip is and solder in a resistor to bypass the contacts in the tumbler. Then use a non chipped key Keeping the chipped key is probably ok as well
Team Owner
Joined: Sep 2003
Posts: 25,394
Likes: 2,741
We just helped a guy solve his "no crank when hot" in his 1992 this past Sunday by reconfiguring his 1992 starter relay wiring configuration to the 1993-1996 configuration. That's all it took.
If this guy has a 1990-1992, I'd begin with changing the configuration to the later wiring that doesn't pass the full solenoid current through the Clutch Safety Switch.
But yeah, knowing the year of the car matters.
If this guy has a 1990-1992, I'd begin with changing the configuration to the later wiring that doesn't pass the full solenoid current through the Clutch Safety Switch.
But yeah, knowing the year of the car matters.
Drifting
Joined: May 2020
Posts: 1,663
Likes: 702
From: Baton Rouge, Louisiana, metro area
The OP says,
”The ignition key has been changed out and there is no chip on the key.” But his chipless key still starts the car.
Evidently sometime ago, his VATS ignition was bypassed and this may not be a VATS issue.
Does this year model have the Security light on the instrument panel like the 90-96’s? I am not familiar with 84-89 dashboard lights.
”The ignition key has been changed out and there is no chip on the key.” But his chipless key still starts the car.
Evidently sometime ago, his VATS ignition was bypassed and this may not be a VATS issue.
Does this year model have the Security light on the instrument panel like the 90-96’s? I am not familiar with 84-89 dashboard lights.
Team Owner
Joined: May 2000
Posts: 53,793
Likes: 5,624
From: Plantation Florida USAF(Retired) 1966-1990
U.S. Air Force
St. Jude Donor '05 thru '26
NCM Sinkhole Donor
Back in the day of the C4, GM had TSB, with customers come plaining no start, like I had, the solution was to replace the ignition switch and new set of keys that go with switch.
After I had it done drove the car for another 14 years, with never problem again.
Yes I had by=pass installed and still gave me problems.
My car was 1989 ragtop automatic transmission.
After I had it done drove the car for another 14 years, with never problem again.
Yes I had by=pass installed and still gave me problems.
My car was 1989 ragtop automatic transmission.
Drifting
Joined: Feb 2016
Posts: 1,384
Likes: 339
From: Simi Valley CA
If there is no chip on the key, does that mean you have an 84 or 85 without the Vatts? If so I would check the clutch safety switch. Those are notorious for causing problems. Most likely you got some sort of loose wiring issue.
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