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Downpipe leak

Deeter

New member
Installed a 3" catted downpipe and used the supplied gaskets. Now I am running lean at wot. The downpipe is leaking at the top gasket a little not audible. So i was thinking a false lean.
However my question is if this leak is after the front 02 sensor why would it cause me to be lean at WOT?

I dont think just adding a downpipe would change the 02 values so much. So much that I started getting 5 kr because of 850 02s, they were 925's before.

Could my 02 sensor just have gone bad/lazy without setting any codes?(still have the rear 02 installed)

Ran 15.1 et's with just adding the downpipe added more fuel 14.7 et's Both avg 2.28 60's

Buick Regal GS

Just frustrated Should have got headers instead of messing around with the downpipe. Anyone want to install headers for me in the Kzoo MI area?
 
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A leak that high up on the down pipe can lead to a false reading by the sensor, or it could be a bad sensor. I'd say try replacing the gasket because you know that is bad, and then go from there.
 
Its a ZZP Downpipe but it is most definatly not the Downpipes fault. Just installation error on my part. Ill Fix it soon.
 
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