02 sensor still shows bad after replacement... plz help

[porsche996tt_tpe]

Hi,

I just had my 2002 tt replaced one of its pre-cat O2 sensors a few weeks ago, but the same fault occurs (engine stalled on low rpm), so the mechanic thought the newly-installed one was defective and put in another new one. After the replacement, he ran the diagnostic, it showed fine, but after a while, it showed near zero volt (where the other sensor was showing about 0.4~5v). He ruled out pressure valve and MAF as potential problems; he also checked out the signaling wires, which seemed to be fine also. Since the sensor is connected to the DME, which he thought might be the problem... It's a costly replacement that I don't want to go through. Anyone who can give me some ideas is very much appreciated...

I was told you can't just buy a used DME and make it work. Its memory needs to be wiped clean and this can only be done by Porsche... Is this true? If it becomes necessary to replace DME, that are the alternatives than buying a new one from Porsche?

Thanks guys.

D.

[Sunnyside]

Hi,

I just had my 2002 tt replaced one of its pre-cat O2 sensors a few weeks ago, but the same fault occurs (engine stalled on low rpm), so the mechanic thought the newly-installed one was defective and put in another new one. After the replacement, he ran the diagnostic, it showed fine, but after a while, it showed near zero volt (where the other sensor was showing about 0.4~5v). He ruled out pressure valve and MAF as potential problems; he also checked out the signaling wires, which seemed to be fine also. Since the sensor is connected to the DME, which he thought might be the problem... It's a costly replacement that I don't want to go through. Anyone who can give me some ideas is very much appreciated...

I was told you can't just buy a used DME and make it work. Its memory needs to be wiped clean and this can only be done by Porsche... Is this true? If it becomes necessary to replace DME, that are the alternatives than buying a new one from Porsche?

Thanks guys.

D.

firstly, what are ALL the codes that he is reading out. Please list them.

Long long before buying a new DME you should have continuity testing of the O2 connectors/wires to the DME plug.

Really it needs to be put on a PST2 or Durametric.

Lets see the codes first.

Edited July 13, 2011 by Sunnyside