QUOTE(terrytcl @ Jan 31 2007, 11:14 PM) [snapback]894965[/snapback]
I have the dreaded P0442 CEL too.
Done everything short of changing the cat.
Someone on the V70R forum mentioned that it may not be a problem with the cat, rather... a problem with an exhaust leak.
I would check around all of the gaskets upstream from the primary oxygen sensor.
depending on the sensitivity of the signals that the ECU is looking for... it may be a problem (the exhaust leak), if measurements among the MAF, primary o2, and secondary o2 sensors are being compared.
My CEL comes back as soon as the drive cycle is complete too. Before coughing up the cash for a new cat, i would check your exhaust gaskets (manifold, turbo, downpipe) and all the emission related vacuum lines.
Did every test by the the book..exhaust, air leaks, smoked the car, comp temp, fuel press test, and today broke down and dropped $750 (my cost) for the cat from volvo, low and behold the light stays off and readiness is fine!!!! Should have known that the $250 aftermarket was a piece of junk Why they bother making some thing that will not work is beyond me, the fitment was fine but the performace stunk!. On to the Next horror show...Thanks all