[93celicaconv]

Given the CEL did come on, there will be at least one code set in the ECU. Get all the codes from the ECU and post them here. They will help a lot narrow down the possibilities.

 

[93celicaconv]

i’m guessing i gotta activate the DLC1 that under the hood to check the code?

 

[93celicaconv]

I got 31 (Volume air flow (VAF)sensor circuit) 41 (throttle position (TP) sensor circuit) and 42 vehicle speed sensor. Parts at the dealership is having trouble finding the VAF which is now discontinued.

Code 31 involves the vacuum system circuit (not volume).

Just remember, the codes tell you what circuits are problematic, not what sensors. It could be the sensors. It could also be wiring that is difective. It could also be an ECU failure. If I understand correctly, you haven't had any problems until that day you were on your way to work. If this is true, it is highly unlikely 3 sensors all failed at exactly the same time. It is possible a rodent chewed the wiring to cause all this. It is also possible the ECU went bad internally to have these 3 circuits affected at the same time. I wouldn't be chasing after replacement sensors right now.

Are you skilled and capable of doing electrical diagnostics?

 

[93celicaconv]

i am not able to perform electrical since i’m not certified and don’t know how to. I was going to put my vehicle in service at the toyota dealership that i work at but one tech knows their way around the celica. Just the downside he’s always busy with warranty work and big jobs

On your own personal vehicle, you don't need a certification. But you would need to be certified to fix other people's vehicles at a service shop. I'm not sure how to help you if you can't do basic diagnosis. I can send you the diagnostic pages for two of those 3 codes you have. If this were my car, I would remove the ECU and open it up to see if the circuit board is pristine or if it has evidence of something that burned up on the board or if it has leaking capacitors. ECU failures were fairly common on these early 1990's Toyota's.

 

[93celicaconv]

Either way i’ll need to work on it myself since it is my only source of transportation due to my honda civic’s transmission blowing itself up since it was a 7th gen auto. It shouldn’t be too hard and yet it does it occasionally like today but it sorted itself out.

Well, let us know what you need for help so this forum can try to assist!