Every now and then my psm and abs lights would come on- there after, the car's idle would fluctuate and sometimes the engine would even stall.

I did a search and decided it was probably a bad MAF. I replaced it but symptoms persist.

I've also read that a worn abs sensor wire could cause similar lights but could that also cause a fluctuating idle?

Thanks

Sameer

 

Does the car fall on its face when you hit boost?

 

Is you upsolute flash designed for k24's?

 

I am getting it after start up once in a while. I drive a little, then restart the car and it's (the lights) gone. I get the whinning noise at start up and some board members think it could be the secondary air pump (whatever that is), it also could be the MAF, I will bring it in soon, but for now it is not affecting performance and it does jump at idle like yours when it happens. I would not worry to much.

 

If you have an Upsolute flash, that could be it. I have one and when i floor it in 6th my car throws the ABS and PSM lights.

 

yes, the Upsolute flash is for the K24's..

 

boost has been fine- I hit 1.2 bar and performance is great....just the wandering idle bugs me a little....it does reset if I turn the car off and on again...

 

I think it happens to us all, it used to bug me, now I don't stress as much, since it does not go into limp mode.

 

I get the same problem occasionally in cold weather if I floor the car before it gets to 80 degrees - hmmm

 

Ouch, that should go in the do's and dont's thread. Flooring the car (unless you are about to get hit by a mack truck) before it has come up to temperature is HORRIBLE for your turbos and engine. I generally sit tight until the idle levels off and then stay out of boost until the temp levels off. It generally only takes a minute or two.

 

Maybe replace 'flooring it' with 'pulling away rapidly from a junction to join a busy road'

 

Yeah, always warm your car up. I have had a couple of new turbos swoosh by me right out of our complex when my engine is cold.Hope their cars are leased because it cannot be good to be at full boost with a cold engine. remember, temp gauge is for water, the oil takes a little longer to reach a good temp.

 

Check the codes. I had a fluctuating idle and the code came up P0507
Throttle body stuck or leak in air intake system. Check the throttle body, I replaced mine and it solved the problem.

 

I had exactly the same problems, i.e., ABS/PSM lights coming on, RPMs that would fluctuate between 750 to 1,200, engine cutting off. I also had a check engine light come on twice that was diagnosed as an idle problem. Oddly enough a new MAF and throttle body was put on about 2 months ago but the problem persisted becoming worse over time to the point that I was about ready to sell the damn thing. Long story short...its your alternator that causing the problems. One of the three phases, more than likely the secondary phase, which was the case with mine, is not putting out enough amperage although it probably is putting out enough to pass the test. When the radiator fans kick on, such as waiting at a light or running in slow traffic, more amperage is needed and the alternator can't keep up. This results in a power shortage to the ABS and PMS systems as well as causing the problems with the variable idle that will sometimes drops to zero resulting in the engine stalling. When I took it down to the dealer I didn't receive much confidence that they would be able fix it as I had it to the dealer several times for the same issues. Fortunately the mechanic had the Chief Mechanic listens to the engine running where he recommended that they bypass the alternator to see if it made any difference. They bypassed the alternator with a battery charger and sure enough the RPMs leveled out. The alternator was replaced and the mechanic took it for a test drive. Even though they replaced the MAF not long ago the mechanic felt that it was still running a little ruff and decided to try another MAF. That fixed the idle problem completely. I've had it back for 3 weeks now with zero problems with the idle, PSM/ABS light coming on or the engine stalling. It runs like it did when I first got it a little over a year ago. I'd almost bet that you have the same problem. Have your mechanic bypass the alternator to see if the RPMs level out. You should be OK as your MAF is new and shouldn't need to be replaced. Good luck.

 

you might be on to something- I've noticed that it does seem to be associated with stop and go traffic- probably when the fan comes on and is never there late night when it's really cold.

I'll get a battery charger and try it myself and report back.

Thanks for such wonderful insight!

Sameer