check engine light problem

[Robert240]

I bought a 91 coupe that runs and drives fine but the check engine light doesnt come on when the key is turned to the on position and this is keeping it from passing smog which is a big problem since i live in California.

The check engine light does work it started off just randomly blinking but now the check engine light will come on then go off then every now and then it will blink randomly.

Am I going to have to replace the ecu or have it sent off and fixed or???

[compactfean]

The ecu is what grounds the check engine light so of it works otherwise, id say ecu will need replaced. If I knew where the check engine light transistor is on the mother board I could run you through how to fix it. I've fixed maf and tach drivers on ecus before, but they usually had something broken that your could see to be able to find what needs fixed.