Hello 3rd Gen'ers...

Got a question for ya... I have a 1991 RS with a 305V8... two years ago It squeaked by on its smog test but only after replacing that cat.

Today took it in and it failed, went to an exhaust shop and they say the cats dead and needs to be replaced...

But the kicker is, the guy at the Smog shop says "I thought these cars were supposed to have another cat, I see the main one here under the passenger seat, but isnt there supposed to be another one? Unless its right at the manifold."

I know nothing when it comes to exhaust but google isnt helping me out much. Would appreciate the help so I dont waste his time and more importantly mine with a retest if its still going to fail.

Thanks in advance

 

Every 305 TBI car came with only 1 cat. Some TPI cars came with 2.

 

Throttlebody here...

Wonder why the damned thing ate through a brand new Cat Converter so fast...

 

There's only the one.

They're STOOOOOPID CHEEEEEEEEP though; if it needs one, just get one and change it out. Put it behind you and move on. Summit is your friend when it comes to thing like that.

 

Move to a better state.

(i.e. one with no testing)

 

Military. I have little say in the matter.

Otherwise I'd be in another state and have strait pipes.

 

Get a magnaflow hi flow cat. That got me to pass.

 

straight pipes are -fun-...for about 2...3 days...

(in a DD)

 

If your 1 or 2 year old cat is already shot, you've got other problems, and just throwing a new cat on the car before every inspection isn't the right way to fix it. You're better off finding why you keep ruining cats. Generally running rich will kill a cat, and the most common reason to run rich is an old/tired oxygen sensor. Sometimes they won't throw a code even when they're no longer functioning properly. The best solution would be to replace the cat, then use a scan tool to monitor engine performance while you drive to try and figure out the real problem. If that's not feasible, at least toss in an O2 sensor when you change the cat if you haven't replaced it in a while.