hello all


i'm new and need to keep this short!

I did a can on my buddy's 91 GT

came up codes 40-12-91
the 12-91

which i guessing is just part of the scan trying again

i know 91 is dead 02 but which one?

12 its idle controller motor acting up?


but whats code 40?

 

any thing?

 

actually the codes repeat, as double assurance that you wrote the numbers down correctly.

here's the codes as follows
"12- system cannot raise engine speed above normal idle"
"91-exhaust gas oxygen (ego) sensor - signal voltage always indicates "lean" either during engine run self-test ("rich" air/fuel conditions) or normal engine operating conditions. OR transaxle problem - shift solenoid 1 (ss1) circuit failure.


alright man thats how it is straight from the book, and as i can see here theres no code "40" cause a code scanner cant beep a zero...
try the codes again if its just a "4" it basically means the self-test is starting..