Foster382

I own a 1991 Firebird Formula 305 V8 tbi. After driving the car for about 5 minutes i get the SES light. So i did the paper clip trick to pull up my error codes and ended up getting 23, 42, 43. what kind of solutions can i do to remove/fix these codes?

Atilla the Fun

Maybe it's time for a new Mustang?

Foster382

I wonder why i didn't think of that first? Wait i do. It's like a people having a nose; everyone has one.

87IROC-DAN61

Hello Foster382!!

Are these all new codes, or is there a possibility that there are some old ones???

If there is a possibility that some are old, I'd erase the codes first, then start up the car, and go for a drive, trying to reset the codes!!

Stop after you get a SES light, and check out which code it is!!

Post back your results!!



If these are all new codes, post back, and I'll see what comes up for you!!!



A new Mustang is not the answer!!!

Atilla the Fun

Well, if the guys who do know your answers won't tell you, maybe they're not guys you should call friends. Me, I don't know. When my LO3 developed problems with the injection, I couldn't get answers, so I just ripped out the entire TBI system.

Foster382

87IROC-DAN61; i did what you said and i only got the code 23. I dont know how 42 and 43 went away; i never did anything to fin them besides replaced the. spark plugs lol. Would code 23 cause the SES light to come on after a few miles?
And if i did end up getting a mustang it would be an 88 Foxbody

Atilla the Fun

Sorry I wasn't very helpful before, you can see I haven't given up on third gens, just on helpful help with TBI. I currently have an '84 Trans Am, and an '89 Mustang. and I think everyone should have one of each. But for those who can't afford that, this is the better chassis to play with.

five7kid

iTrader: (14)

A trouble code will clear after 50 (or some high number) ignition on/off cycles after last being set. Had you set the timing sometime in the near past?

The 23 should be the inlet air temp. Have you fussed with the air cleaner?

Foster382

Im not all that car smart. My auto-tech teacher said someone had advanced the timing abit on the car. I did spray throttle body cleaner on that sensor to clean it. Maybe it was to cold for it?

87IROC-DAN61

Hello Foster382!!

Spraying anything, especially throttle body cleaner on a sensor is a no-no!! Sensor internals don't like liquid, nor solvents!! Spray the cleaner into/on to a rag, then use the rag to clean the sensors!!

Check for a broken/chaffed/disconnected wire to that sensor, if you can't find any, replace that sensor!!

Best of luck!!

87IROC-DAN61

Hello again Foster382!!

The other codes could reappear shortly, or they could be gone for good, due to other factors, hopefully that is the case!!

Yes, code 23 could cause the SES light to come on after it goes into closed loop mode (after a few miles)!!

No Mustang!!

Foster382

seeing that their are no wire to this sensor, just 2 vacuum tubes. can't i cap off the vacuum line?

five7kid

iTrader: (14)

You aren't looking at the correct sensor. One has wires, the other has vacuum lines.

I H8 WWD

iTrader: (5)

Check here for info on the IAT, Intake Air Temperature Sensor.
https://www.thirdgen.org/forums/tech...r-element.html

five7kid, remember how I said I had no SES lights come on when I bought the car which later found out the IAT was unplugged, maybe because I only drove the car a little bit and it didn't have time to go into closed loop? It did have time to overheat and such but, maybe not long enough to pop the SES on?

ibmtech

iTrader: (1)

Isn't it kinda ironic that the Code 42 & 43 both have do with timing

42 Electronic Spark Timing or Bypass fault

43 Electronic Spark Control fault

Especially since he stated that someone playing with the timing on the vehicle.

five7kid

iTrader: (14)

No, it's not ironic. It's why I asked.

Foster382

well my TBI air inlet looks like this:
I only see the sensor for the vacuum lines.

Chris67rs

i know this is old but i had the same issue,

Code23 could be one of 3 things, mine was the first

1: TPS sensor malfunction
2: IAT sensor
3: Manifold Air Temp sens

tps was 13$ at autozone and 2 hex bolts and a wire. boom back in action.