TCS off light coming on?
#23
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Originally Posted by Bad30th
A bad ground on the battery, back of the heads or on the front/sides of the engine compartment can cause this.
It can also be caused by cam/tuning/intake airflow increases.
With a bigger cam than stock the PCM sees more air at idle than it should for a given throttle percentage and thinks the TPS sensor is whacked so it disables the traction control (and the switch won't enable/disable), and it falls to speed density when this happens.
If this is the problem you will often throw a P0121 TPS code. Replacing the TPS will not fix the problem, as the TPS is fine.
Raising your idle speed with tuning software (or EFIlive can adjust the actual expected idle airflow vs TPS) will normally mask the airflow reading problem enough to not throw the code and experience the TPS problem.
Cheers,
Rob (Bad30th)
It can also be caused by cam/tuning/intake airflow increases.
With a bigger cam than stock the PCM sees more air at idle than it should for a given throttle percentage and thinks the TPS sensor is whacked so it disables the traction control (and the switch won't enable/disable), and it falls to speed density when this happens.
If this is the problem you will often throw a P0121 TPS code. Replacing the TPS will not fix the problem, as the TPS is fine.
Raising your idle speed with tuning software (or EFIlive can adjust the actual expected idle airflow vs TPS) will normally mask the airflow reading problem enough to not throw the code and experience the TPS problem.
Cheers,
Rob (Bad30th)
#24
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Originally Posted by senicalj4579
so let me get this straight, if i take my vinci/crane tuner and raise my idle rpm, the whole problem with the p0121 code and traction control will be gone?
The higher idle RPM sometimes straightens out the expected airflow somehow, at least it bandaided it for me... Mine was ~900-950 when I had my cam. I'm running an LS6 cam now, no problems.
Rob (Bad30th)
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Originally Posted by senicalj4579
i'll try that. but what if it dosent work? does everyone else have the same problem as me? i put the car in drive and it surges on and off
If the car is surging it needs to be tuned better, I don't see a cam in your sig - I also see you have ported MAF ends, put the screen and stock MAF back in and I bet it helps a lot.
Rob (Bad30th)
#27
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correct, no cam. everything was fine for 3 years untill i installed my ls6 intake yesterday. also i compleatly removed my egr and air with air pump. also during my install i ripped out my map sensor wires out of the harness and tried to repair it. seams like i fixed it because theres no codes for the map. do you think that besides the bigger intake that the egr,air,or my map sensor wires have something to do with it at all? i'm hoping my map is fine