blueline

I need some help diagnosing a problem. My 01 TT doesn't always produce high boost pressure. It produces around .9 Bar during the first few (3rd, 4th, or 5th gear) WOT runs, but then mysteriously, won't top .5 Bar until I shut the car off and let it cool a bit. I'm taking a risk that the cops will nab me every time I test it.

Background -
01TT w/ 8,000 miles
Upsolute ECU upgrade
New EVO DV's
New FR6 plugs
New MAF sensor

problem first surfaced after replacing the factory DV's. Could a bad DV cause this behavior? How would I know?
OEM turbo pressure hoses have come loose, but were reconnected. I know there are upgraded hoses, but I'm not sure this is the problem.

Any ideas? Thanks in advance for the help.

Chris

PorschePhD

It is going into limp mode. Have the pending DTC checked.

blueline

Stephen,

Thanks so much for your help.

I ran the car hard this morning and got a PSM/ABS light followed by PSM/ABS/ CEL. I had the codes read which are P1250 and P0103. These are the same two codes as I had last time I got the PSM/ ABS fault.

I contacted Rene at Upsolute and he said he wants to install a revised program since I have a new MAF sensor. It's something about allowing a broader range of values accepted from the MAF. I'm taking it to him next week. I hope that fixes it.

BTW - I think your on target with the limp mode idea since iit matches my experience. Thanks for that. My dealer didn't put two and two together when I repeatedly told them about the .5 Bar limit that seems to happen all to often.

The following is the entire history of the issue I'm having:

I upgraded my ECU to Upsolute's program last October. Shortly after that I got a PSM and ABS fault, but it didn't repeat for a while. Then in December, I had the spark plugs and diverter valves replaced as a preventive measure. Shortly thereafter I got a PSM/ABS fault, and then a PSM/ABS/CEL. The dealer in Charleston, SC where I was at the time diagnosed and reattached "loose turbo pressure hoses" and reset the CEL. After that I began to notice times in which the car would not produce over .5 Bar of boost, where it normally produced .9 Bar. I have since had several PSM/ABS events and numerous times where the maximum boost is limited to .5 Bar with no indicator lights. Last week Hendrick Porsche diagnosed a bad MAF sensor and replaced it. This morning while testing the car, I got a PSM/ABS fault, then a PSM/ABS/CEL, after which the max boost was limited to .5 Bar.

Thanks to all who reply.

markski

from the look of things.... u might want to consider a more reputable tunning company that doesnt give so many problems.... aspecially maf issues...
... a few guys told me that they get cels in cold weather... especially winter(with absolute prgram).

NC Bob

Don't think it's the Upsolute. I've had mine in for three years and never had a CEL and never had it upgraded. I'm guessing the DV connections are one of the problems.

markski

Upsolute is fine but a bunch of guys complain that in cold climates it throw cel lights.... something with MAf issues.... otherwise its fine for what it is.