Check engine light, on freeway
Thread Starter
Instructor
Joined: Dec 2003
Posts: 205
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From: Cupertino ca
Check engine light, on freeway
my 96 LT4 is having some issues... when im in 6th or even 5th gear at a low RPM at higher speeds (on the freeway) and when i give it more than 50% throttle ruffly the check engine light comes on. the code says check maf operation and the MAP... so the maf sensor checks out, and the MAP sensor does aswell. the diagnotstic computer said replace the map, and we did. But it still came back... what could be causing this to happen... nothing feels wrong with the car either, it runs perfectly smooth and normal all the time. any thoughts? I have to fix this problem so i can sell the car.
Thread Starter
Instructor
Joined: Dec 2003
Posts: 205
Likes: 0
From: Cupertino ca
that is the first thing im going to do next. I had a really well known corvette specialist do the work for me. He hooked up a tool to the diagnostic port and displayed live feed from the computer. The MAF was running at 7.93 G/S and he used a huge computer with all the wires to hook up.. i thought it was called a diagnostic computer. But he did everything right, also another possibility we thought was an O2 sensor but that checked out to.
Last edited by CaliforniaVette; Sep 17, 2004 at 12:51 AM.
Burning Brakes
Joined: Aug 2001
Posts: 1,238
Likes: 0
From: walled lake MI
might want to see exactly what codes you got. for OBD-II there are several types of failure modes for each sensor, and i think there are some "rationality checks" that are done to compare sensor readings to see if they make any sense even if they are in correct operating voltages.
Advanced
Joined: Feb 2004
Posts: 51
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From: Mission Viejo CA
I would also check the weather-pack connectors on the MAF. I had a MIL and a code P0100 and P0102: Both indicate some sort of problem with the MAF. OBD-II is nice; it tells you what area to check to solve your problems. I recalled that I had a problem with connectors on my old IROC. I straightened the pins and slightly crimped the female connectors and voila! Cheap fix and no more MIL in about 3 months of driving. Good luck!
Burning Brakes
Joined: Jun 2003
Posts: 827
Likes: 1
From: Henderson NV
Another suspect on the list is the electronic spark control module. Not sure if your model has one, but I expect it does. Folks sometimes change out the knock sensor without good results and the code 43 can be elusive.
