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.

 

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

 

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?

 

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.

 

Jumping in late....
You mentioned that the CEL goes off when you let off the gas. A CEL code typically won't reset until a number of drive cycles or types of a drive cycle are finished.

If the car is dropping rpms, the ECU will either
A) start receivingv weird signals from the sensors
B) think it's in a starting mode, and do a dashboard light test.

The heavy exhaust smell suggests there is too much fuel it there is unburnt fuel. Either of these could cause the engine to not perform well and could lead to low rpms.

 

So after testing the sensors the tps was faulty, and the map sensor was going out due to some faulty wires. Ended up replacing the tps and cleaned the map sensor and had a friend help me replace some wires(thank god he knows what he’s doing). I did get a new map sensor luckily by a friend for cheap. Had the ecu cycle a bit yesterday and today and will say i have seen improvements and haven’t had the rpms drop like crazy or have the engine sputter like how it was recently.


I’m not certain if this fixed it, and will do more testing and driving to be positive this solved it.