Fuel pump and CEL

[georgeb]

I've only done the engine off one. The other is to set the timing and idle.

[freshtiva]

I switched ECT ( engine coolant temp sensor ) with one in a spare motor. No more surging and no more CEL ( check engine light ) Frankenstiva is purring like a kitten once again. Easy fix thanks to my new favorite home made tool. I guess the ECU didnt know the motor was warmed up and feeding extra fuel to the injectors then the fault parameters would correct causing the surging. At least thats my story.

[BigElCat]

Far Out!

Will the CEL on the carby Festivas blink the codes, also? I always use a multi-meter. Are all OBD 1 systems like that?

[blkfordsedan]

Congrats!!! Ahhh.....the wonderful world of self-diagnostics! If only we could flash tune these things via an OBD port!

[georgeb]

The carbies work the same. On our OBD1 BMW you stomp the gas pedal 10 times to bring up the code. Called the "stomp" test.

[freshtiva]

Im wondering if you can do a switch monitor test by grounding the STI and watching the CEL without using the multimeter on the SML ( switch monitor lamp ) pin of the STO.

[Justin]

cool tool! I gotta try that one, just bought some aligator clips too..glad you figured out the intermittent issue.

[Justin]

No, none of my fuel pump failures threw a CEL.
But, also none of them failed in the way you describe.
They ran fine, then on the next start-up "no go".
I'm thinking your issue could well be somewhere else.

My car ran fine yesterday & would'nt start this morning until I pumped the pedal like a carby! so This is most likely the way these pumps go.

[freshtiva]

Congrats!!! Ahhh.....the wonderful world of self-diagnostics! If only we could flash tune these things via an OBD port!

Thanks

I bought a festiva breakout box years ago but never had the brains or the need to figure out how to use it. Wish it had come with instructions. Fortunately you can gather a lot of self-diagnostics w/o it.