BLUF: TCS & CEL come on when close to redline and engine reverts to safe mode (rich AFR's & lower redline)
I'll try to make this as simple as I can
Symptoms
When accelerating, the TCS & CEL come on at the same time usually between 7500-8000RPM, afterwards the engine reverts back to a really rich fuel mixture and the redline caps around 3000-4000 (can't remember exactly). This doesn't happen every time, and usually occurs in 2nd-3rd gear. I can restart the car and everything is back to normal.
Car Details
1991, 62,000 miles, low boost CTSC (lysholm), headers, BBK, and most of the other common bolt ons. O2 sensors and spark plugs recently replaced.
Codes
CEL 16 - Fuel injection: Not sure how old this code is, but doesn't really make sense. I just replaced the main relay, igniter, fuel filter, and had the OEM injectors rebuilt and flow tested.
TCS 31 - Engine Control Module: I'm guessing this is a different name for the ECU, it's not chipped or anything, only the signal modifier from the CTSC is plugged in.
TCS 34 - Abnormal VREF: Has to do with some kind of reference voltage? Note: the tachometer/speedometer are acting normal.
What I've found so far
Initial symptoms would lead me to believe a bad ABS sensor (wheel speed sensor) however the TCS didn't give me any "4" codes to indicate that. Second guess might be a bad vehicle speed sensor, but that would have accompanying speedometer abnormalities (fluctuating/drops to zero) which I don't have. From the codes I can guess it has something to do with an electrical problem related to the wiring (battery cable, ecu harness, tcs harness, or fuze?) and not so much a faulty sensor. That's really just a guess though.
Thoughts/recommendations appreciated! (Larry where are you )
Edit: i will replug the ecu, tcs and pull the clock fuse and see if I can get any different codes/results.
I'll try to make this as simple as I can
Symptoms
When accelerating, the TCS & CEL come on at the same time usually between 7500-8000RPM, afterwards the engine reverts back to a really rich fuel mixture and the redline caps around 3000-4000 (can't remember exactly). This doesn't happen every time, and usually occurs in 2nd-3rd gear. I can restart the car and everything is back to normal.
Car Details
1991, 62,000 miles, low boost CTSC (lysholm), headers, BBK, and most of the other common bolt ons. O2 sensors and spark plugs recently replaced.
Codes
CEL 16 - Fuel injection: Not sure how old this code is, but doesn't really make sense. I just replaced the main relay, igniter, fuel filter, and had the OEM injectors rebuilt and flow tested.
TCS 31 - Engine Control Module: I'm guessing this is a different name for the ECU, it's not chipped or anything, only the signal modifier from the CTSC is plugged in.
TCS 34 - Abnormal VREF: Has to do with some kind of reference voltage? Note: the tachometer/speedometer are acting normal.
What I've found so far
Initial symptoms would lead me to believe a bad ABS sensor (wheel speed sensor) however the TCS didn't give me any "4" codes to indicate that. Second guess might be a bad vehicle speed sensor, but that would have accompanying speedometer abnormalities (fluctuating/drops to zero) which I don't have. From the codes I can guess it has something to do with an electrical problem related to the wiring (battery cable, ecu harness, tcs harness, or fuze?) and not so much a faulty sensor. That's really just a guess though.
Thoughts/recommendations appreciated! (Larry where are you )
Edit: i will replug the ecu, tcs and pull the clock fuse and see if I can get any different codes/results.
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