TCS off and reduced engine power lights

[brandon684]

My car has been doing this weird shut down thing. Every once in a while, the reduced engine power and tcs off lights will come on, and the car will absolutely refuse to run. After turning it off for a few minutes, it will eventually run again, but it sure is a pain in the ***! Anyone have any ideas? I have headers with high flow cats and the o2 simulators, if that would make any difference. I believe it has only ever done it to me in warm weather.

[kristen]

Re: TCS off and reduced engine power lights

no ses light???


i would start by cleaning your maf sensor...

[LoveMy02W68]

Re: TCS off and reduced engine power lights

I've been having the same problem lately. Idk what the heck is causing it but my reduced engine power light will not go off at all. I checked my MAF sensor and it looks fine. I don't have an MAF screen though. But it's been out for a long time and I've never had this problem. I do however have my check engine light on for a bank 1 o2 sensor. But that's not a first either. And other ideas? If I can't figure this out ill have to just take it to the dealer and pay the shot to fix it :(

[J Phillies]

Re: TCS off and reduced engine power lights

what year is your car? ... if it is a drive by wire car, check the position sensor ... seems to be a fairly common thing

[Rob Bell]

Re: TCS off and reduced engine power lights

I agree with J Phillies.... the Reduced Power function is there as a safety feature in case something goes wrong with the electronic throttle so you don't kill yourself. Check that area for loose or dirty connections , frayed wires, blah blah blah. Good luck.

[Leonard 3.8L]

Re: TCS off and reduced engine power lights

MAF, coil pack? Anways, good luck.

[LoveMy02W68]

Re: TCS off and reduced engine power lights

its a 2002. I'll check the position sensor. I have a ZEX nitrous kit tapped into the TPS so that might be it, but I've had the nitrous a while and this has never happened before. I'll still check it out and let you all know what I find. Thanks all.

[Meatyshells]

Re: TCS off and reduced engine power lights

fuel pump, check the fuel pressure

[J Phillies]

Re: TCS off and reduced engine power lights

from reading this thread i think there is a misunderstanding about what the Reduced Engine Power light represents.....


the light comes on because the computer has reduced the power of the engine due to some malfuction in the system ... its a safety thing....

it doesnt come on to tell you "your car in running like crap because you have a misfire or you're not getting enough fuel"

most of the time it's the tps...

[Blizzard242]

Re: TCS off and reduced engine power lights

I had that happen once while I was on a Michigan highway of all places.. pulled over, turned the car off for a few and it never came back again. That was in my 02 so the TPS idea sounds alright to me. It only happened once though in all the years I've had it. I can only tell you it was hot as hell out that day so I had the AC cranked. Maybe the TPS is sensitive to heat.. just a theory.

[LoveMy02W68]

Re: TCS off and reduced engine power lights

so heres what i found. I checked the spark plugs and the wires. both are good. Checked the vacuum lines and the manifold vac and everything is good, altough my vac gauge is a little jumpy. checked the TPS and where the nitrous taps into it. everything checks out ok. So I just pulled the codes, P0420, bank 1 o2 sensor. Erased all the codes. Been driving it a bit and so far no reduced engine power light or check engine light. The drive cycle hasnt fully completed yet so I'm sure it will come back. But so far erasing the codes is working because before it would idle really hard and I couldnt even start the car without the reduced engine power light coming on. So i'll keep an eye on the monitor and see what is triggering it. Thanks for everyones help, i'll keep you posted