Your car should have a separate cat for each bank of cylinders. The bank 2 cat will be the one under the hump in the floor on the passenger side. The bank 1 cat will probably be attached directly to the bottom of the manifold on the drivers side. Code P0430 would indicate a bad cat, but it wouldn't hurt to try just clearing the code to see what happens. You would be supprised how often you can clear a code and they don't come back for a long time.
Gary
Hello. Here is my situation. Opinions and advice solicited:
>
> - I have a 2001 Z28 with an LS1 in it.
> - Very recently the SES light came on.
> - Car seems to run fine, no noticeable change.
> - Had it scanned for codes at a parts store.
> - Code thrown is P0430, Catalyst efficiency below threshold (bank 2). >
> I'll throw these in also for completeness but separate them because
> they may run the risk of distracting from the real issue:
>
> - Approximately a week or so prior to code coming on, I put the
> proscribed amount of Sta-bil fuel stabilizer in the tank. I put it in
> a quarter full tank then did a complete fill up to mix it as best as I
> could. I sometimes do not drive the Z28 in the winter months much at
> all and I was concerned about the fuel getting too old over the
> winter. This is the 1st time I have used this product on this vehicle
> but have used it in the past on other things. I have put a fresh 3/4
> of a tank of fuel in since and have not added more Sta-bil. I have
> been hoping the problem would go away but hasn't.
> - Many months ago I needed to have an air pump check valve replaced
> and I replaced both sides. No problems after doing so (until now).
> - Ever since I have owned the car I have always thought the exhaust of
> this car smelled a bit like, strangely enough, like the smell of
> freshly fired ammunition. Whereas I haven't really thought that of
> any other exhaust so much. Other exhaust has always hinted more to me
> of burnt up gasoline (big surprise there).
>
> I believe that my exhaust is configured in this way: exhaust for each
> two banks of four cylinders is an exhaust manifold which leads to a
> common catalytic converter with oxygen sensors for each bank before
> hitting the catalytic converter and a sensor in common after the > converter.
>
> My understanding of how this code might be generated is that the
> computer will evaluate the catalyst efficiency by comparing the oxygen
> sensor readings before the cat and after it. My "logic" therefore
> dictates that a likely problem is a failing oxygen sensor in the
> exhaust stream coming off bank 2. If the catalyst itself was actually
> not working, wouldn't codes be thrown for both banks? If there were a
> problem with the sensor for bank 1, wouldn't the code be thrown for
> that bank? If the common oxygen sensor after the cat were bad,
> wouldn't it think both banks were bad? Must the answer be
> fouled/failing sensor in bank 2 exhaust stream? Am I completely
> missing something? Thoughts? I am tempted to just go and buy a new
> sensor (or set of them) and install but before I do I would value the
> advice of some of you so I don't waste any more money or time than I > have to.
>
>
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