Well Doc, was driving to the dealer and low and behold the check engine light goes on 2 Km's before the dealer so I did a quick scan of the businesses and there stood a private service station so I went in and had him do a reset for me and returned the truck to GM off lease, and picked up my new truck, thanks for all your help with this old pig of a truck, the worst truck I have owned yet (2000 GMC Sierra Z71 Loaded) too many things went wrong with this one, thousands of dollars wasted repairing it.
> > Very confusing answer I might add, were you talking to me! Haha >
> Paul,
>
> If the 02 sensor has been replaced and it's still reading "catalyst system
> efficency below threshold" on the same bank, it's most likely just that,
> your catalytic might be shot. The post-cat 02 sensor looks at the
> difference in 02 content between itself and the pre-cat sensor on the same
> bank to measure cat. system efficiency. Your cat is still under warranty,
> even if yer' truck no longer is. I'd take it to the dealership and DEMAND a
> new cat.
>
> If she's going to be traded in, reset the PCM just before you leave to bring
> her in so the cat. and tranny problem don;t scare them away! Regarding the
> Tranny code, was it P1870? Very common on the 4L60e's, and it means it's
> time for a rebuild.
>
> Doc
>
> >
> >
> > > ..............
> > >
> > >
> > > O2 Sensor bliss
> > >
> > > Group: alt.autos.4x4.chevy-trucks Date: Wed, Jun 18, 2003, 7:33am
> > > (CDT-2) From: snipped-for-privacy@not.me (PAUL)
> > >
> > >
> > >
> > >
> > > we decided to replace that particular sluggish O2 sensor, and do a
> > > reset. Problem dissappeare for two days then came back.
> > >
> > > I did a battery terminal removal type reset yesterday and everything
> > > seems ok for now but I am a bit worried that the light is going to come
> > > on just as I turn into the parking lot of the dealer where I am going to
> > > turn the truck in this friday.
> > >
> > > Would it be advisable to do the power down reset just prior to
> > > returning the truck to hopefully not have the light come on just as I am
> > > returning the truck. I also realize that the emmision controls are
> > > warrantied still but I am just hoping that the dealer is not going to
> > > give me a hard time.
> > > ===============================
> > >
> > > Unfortunately this is a moral question....
> > >
> > > so I will have to referr you to God for
> > > an answer......if your concience won't give you one.
> > >
> > >
> > > .gibson6string..
> > > bet's ole Paul would be the first one to throw the stone.....
> > > =================================
> > >
> >
> >
>
>