So I just bought the 4th V8 Stang I have ever owned, 3rd 5.0. It has 49k miles. Immediately I put new plugs, wires, cap, rotor, air filter, fuel filter, oil and filter, and brand new IAC from Ford. She is 100% stock underhood, o/r x-pipe, flowmaster catback, and 4.10 gears (assume). Problem is when she is cold. I think she is running REAL rich until I drive 3-4 miles, then the problem vanishes. She idles great when warm. What do you all think? AutoZone cant pull OBD1 codes. It cant be much, ITS STOCK! EGR? And the check engine light will come on sometimes, then go away, then sometimes not come on at all. Thanks for your help
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The computer will still store temporary codes like that - pull codes and see what you get. Have you cleaned the MAF? A dirty MAF will make the engine run like crap. Might also be worth running Seafoam through the engine to clear out any of the gunk inside.
Sounds like a sensor problem. The o2 sensors don't run until the car is up to temperature. Sounsd like it is running real rich until the O2 sensors turn on and adjust the mixture.
Kurt
Kurt
Ok, I pulled the codes...this was the first time doing this. I ran a wire and read them off the flashes of CEL. I spent an hour repeating, so I feel they are accurate. Heres the list.
17 RPM below self test limit
73 TPS sensor did not exceed 25% rotation
61 ECT has intermittently failed below .2 volts
77 system failed to recognize brief WOT during DR test
33 EGR valve opening not detected
42 HEGO sensor circuit indicates system rich rt side
43 HEGO lean at full throttle
25 knock not sensed during dyn. test
WTF does all this mean?
I have also replaced coolant temp sensor and cleaned MAF when I bought her. Why do I have so many codes!? Where should I start?
Thanks again.
17 RPM below self test limit
73 TPS sensor did not exceed 25% rotation
61 ECT has intermittently failed below .2 volts
77 system failed to recognize brief WOT during DR test
33 EGR valve opening not detected
42 HEGO sensor circuit indicates system rich rt side
43 HEGO lean at full throttle
25 knock not sensed during dyn. test
WTF does all this mean?
I have also replaced coolant temp sensor and cleaned MAF when I bought her. Why do I have so many codes!? Where should I start?
Thanks again.
The 94-95 V8 does not store 2-digit codes, it only gives 3-digit codes. If those digits are in the same order as the flashes on the car, your codes are:
172 O2 Sensor Lean condition
533 EIC Circuit Fault (never heard this one before)
135 (unknown)
given the unknown code, you may have read them incorrectly. I would invest in a cheap code reader that will count the blinks for you; it's much easier IMO.
Let's worry about the KOEO (key on engine off) codes first, then move on to the KOER (key on engine running) codes.
172 O2 Sensor Lean condition
533 EIC Circuit Fault (never heard this one before)
135 (unknown)
given the unknown code, you may have read them incorrectly. I would invest in a cheap code reader that will count the blinks for you; it's much easier IMO.
Let's worry about the KOEO (key on engine off) codes first, then move on to the KOER (key on engine running) codes.
really? damn, for some reason I assumed they were 2 digit codes. Gonna pull some new ones tomorrow. It is so strange how it is running. Now, when I first start her and take off she runs fine. Revs fine, holds idle, etc.. THEN maybe 3 minutes after she is running, it reoccurs. After maybe another 3 minutes of driving it clears up and runs great. Keep ya posted!
