Check Engine Light Diog Flash Code

[gambit]

My check engine light comes on all the time, and I shorted out the computer plug to find out the issue and it flashes 23. Anybody know what sensor that is on a 1981 corvette with automatic and air?

 

[gmjunkie]

Code 23
Manifold air temp (MAT) sensor-signal voltage is low or high,
or
Throttle position sensor (TPS) error,
or
Mixture Control (M/C) solenoid open or short circuit problems

The old ecm's are purdy Stone Age and cover 2 or 3 things!! You'll just have to check them all till you find it!!

 

[gambit]

My brother, a mechanic, told me that with these three, you could narrow it down. When you short out the Diag Plug to get teh codes to flash, you should hear a rappid repeating clicking in the carb area, which is the M/C clicking. If you dont hear that, then that would be your first obvious choice as a replacement. Im going to look into it today.

 

[Shaggyvette]

Try disconecting the neg. cable on the battery to re set the ecm. Then check your codes again. I find that my 82 shoots a code then when I re set I'm ok for a couple of months. (got to love the older ecm's). Just my .02cents.

Dave

 

[Sensei]

Before you reset by unplugging the battery, check the connection on the carb (black plug on top of carb). Then reset. If that does not fix it, there is a flow chart for trouble shooting code 23 in the GM service manual (pg 6E1-21). Someone may be able to post it for you, but having one of these books is a must if you work on your car (also if you have someone else work on it for that matter). You can find them on e-bay for around $50. I was patient and got mine sans front cover for $9! God bless, Sensei