tylerwerrin

Hi guys,

I posted on the PCM diagnostics forum earlier. After i reviewed my TTS Datamaster data more thoroughly, i noticed some compelling evidence that would seem to indicate an exhaust leak, or some kind of problem with my O2 sensors.

In Closed loop, my Short Term counts and Long Term counts both read a perfect 128 -- they don't move at all. As soon as my car enters closed loop, the LTerm counts drop immidiately, down to 110 and even 108. They move up and down upon acceleration and deceleration, but not much. The Sterm counts are more consistent and tend to stay above 120 although they dropped down to 115 a couple times upon fast deceleration.

Sooo, judging from that info, I would think there is an exahust leak that is letting excess oxygen into the downpipes. I just had some exhaust work done on the car a few months ago (new gasket & brass nuts & studs). The O2 sensors are very new too, although they may be fouled now after running so rich for the past 500 miles or so.

What do you guys think? Should i take it back to the exhaust shop? I'm using Rams Horn manifolds, with custom made downpipes. The manifolds are torqued down sufficiently and there are new exhaust gaskets. I believe the leak would be around where the flange of the downpipe and the manifold's center dump meet. Is there a way to test for this? Or a way to possibly seal this up better if that is truly the problem? Or do you think it is something else?

Any help would be very appreciated!