Our 88 Wagon needs some exhaust system repairs. I'm not sure if the O2 sensor needs replacing, though I might just get a new one anyway, and not run the risk of ruining a new CAT. I tested it and I get the .5 constant readout, but not much fluctuation; however, I'm not sure if it was hot enough, and the Bentley and Haynes are in disagreement over whether to leave the O2 sensor connector on or off when testing. I'm going to try it both ways. Either way, I can decide what to do about that on my own. I need some opinions on these other matters.

I have many questions but I'm thinking that I should just tell you what the condition of the exhaust system is like and let you guys tell me what you would do. The CAT is definitely rattling. And I live in a state that has emissions testing. No question I'm better off with a new CAT. I was at the yards recently - nothing but junk, re CATS. Better to get a new CAT, right? Anyway, I became aware of Starla, Bosal, and of course Volvo OEM (is it OEM?), via, the archives. Any preferences? Why?

The piping all looks ok, except for one spot with a small hole, which has returned (I fixed it last year with a muffler repair kit. Passed emissions. This year I want to fix it right). The hole is in the very last part of the pipe routing, right at the entry point going into the second muffler. On this wagon it is a small elbow section that is separate form the longer section in front of it. I think it might have been modified by the previous repair shop, because pictures I see do not have a separate small elbow pipe there, they show a pipe that goes from the rear muffler forward to the next muffler, if I remember correctly. Anyway, putting a smaller pipe there might not be such a bad idea, form what I read about the constant rotting at this spot on 240's.

Enough, you get the picture. Tell me what to do. My thoughts are to get this small pipe replaced in Stainless Steel? Double Galvanized? or Aluminum?

Btw, do I have to have two mufflers on the car. Wouldn't one muffler suffice? Is it legal to change it? Other cars only have one. What's the purpose of two?

The front muffler looks okay. The rear one for the most part, except for the seams looks okay. I can't determine whether the seams are rotted or not. There is rust there, though. Another thing I need to check further. Perhaps I can get a partial opinion on the info I presented today and then have another look at it and report back to whoever seems the most qualified to help me, if I find anything else.

So, it adds up to one new CAT needed, a small rear elbow pipe; oh, and I think a front bracket of some kind is missing from the car, at the point where the exhaust manifold meets the piping, at the frame of the car. There was something there that was removed by previous repair shop. Don't see any heat shields except for the one above the CAT. That's about it. Could be much worse, actually.

Not sure about on the O2 sensor or the rear muffler. Should I postpone these questions and investigate further? What more can I do to check the rear muffler? Thank you all in advance, Bruce