This seems too good to be true:
https://www.ebay.com/itm/135199870360?f ... BMnrXI6cRm
Exhaust replacement - Cat/resonator flange rotted out
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vtl
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New OE DP costs exorbitant money. The affordable ones are made of thin cheap steel and cheap ceramic converter, which your rear oxygen sensor will dislike. I have a good quality 3" downpipe that has a cheaper converter, and the only reason I don't get a cat efficiency code is my ECM tune that ignores the downstream sensor altogether. But I can tell by smell that this aftermarket CAT is not anywhere near the expensive metal one that Volvo used.
Bring a 6-pack to your FIL, welding an old car with a relative is a good bonding experience
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JayPea44
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Yep the OE ones are thousands and the price of affordable one makes me think they're essentially junk. I'm going to go with some kind of bracket to hold it together for now then have the FIL weld it when he can. He's retired now so needs something to dovtl wrote: ↑27 Oct 2025, 10:57New OE DP costs exorbitant money. The affordable ones are made of thin cheap steel and cheap ceramic converter, which your rear oxygen sensor will dislike. I have a good quality 3" downpipe that has a cheaper converter, and the only reason I don't get a cat efficiency code is my ECM tune that ignores the downstream sensor altogether. But I can tell by smell that this aftermarket CAT is not anywhere near the expensive metal one that Volvo used.
Bring a 6-pack to your FIL, welding an old car with a relative is a good bonding experience![]()
- jonesg
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those split couplers are rather flimsy, I bent several of them before finding something more solid, same idea. (link below).JayPea44 wrote: ↑27 Oct 2025, 11:05 Looks like I don't have to make it myself - this is exactly what I was envisioning.
https://www.autozone.com/emission-contr ... 110783_0_0
You will very likely need longer bolts, stainless.
Clean the flange mating surfaces with a hand held belt sander (it can be done in place but use goggles)
hi-temp RTV , I doubled up the gasket, glued together with a thin smear of RTV overnite.
Support the joint when doing the final cinch up, I used a trolley jack sitting on a milk crate to lift it into alignment then final tighten the nuts.
Be aware the pipe might measure the typical 2.5 inch but theres a raised reinforced shoulder at the flange so get that measurement, not the pipe itself.
VTL is right about buying a mig, especially with a weldor in the family to teach you.
With all the horsing the system around I broke the flex pipe and had to weld a new one in.
I had to buy a tank of argon/C25 gas as flux wire burns hotter and I couldn't see the weld joint.
this link is for flat oval pipe, find the one for round exh pipes instead .
Can't recall if the pipes are flat oval or round, its been 2 years and it held up fine.
https://www.amazon.com/EVIL-ENERGY-Exha ... 9hdGY&th=1
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vtl
- Posts: 4723
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Need a better helmet? This one is freakin' awesome, I can see everything now: https://www.amazon.com/dp/B076H4MWDS
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VanBoisvert
- Posts: 2
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- Year and Model: 1995 Seat Marbella
- Location: USA
Troubleshooting Volvo electrical issues can be tricky, especially with older models. Keeping track of wiring diagrams makes things much easier. Between research sessions, I like to unwind a bit on https://casinosanalyzer.com/free-slots- ... yal-Riches ; a short break like that helps me stay sharp while analyzing problem areas.
Last edited by VanBoisvert on 04 Nov 2025, 01:31, edited 3 times in total.
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JayPea44
- Posts: 61
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- Location: Detroit
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Thanks - that's the exact ones I have in my amazon cart right now.jonesg wrote: ↑27 Oct 2025, 19:29those split couplers are rather flimsy, I bent several of them before finding something more solid, same idea. (link below).JayPea44 wrote: ↑27 Oct 2025, 11:05 Looks like I don't have to make it myself - this is exactly what I was envisioning.
https://www.autozone.com/emission-contr ... 110783_0_0
You will very likely need longer bolts, stainless.
Clean the flange mating surfaces with a hand held belt sander (it can be done in place but use goggles)
hi-temp RTV , I doubled up the gasket, glued together with a thin smear of RTV overnite.
Support the joint when doing the final cinch up, I used a trolley jack sitting on a milk crate to lift it into alignment then final tighten the nuts.
Be aware the pipe might measure the typical 2.5 inch but theres a raised reinforced shoulder at the flange so get that measurement, not the pipe itself.
VTL is right about buying a mig, especially with a weldor in the family to teach you.
With all the horsing the system around I broke the flex pipe and had to weld a new one in.
I had to buy a tank of argon/C25 gas as flux wire burns hotter and I couldn't see the weld joint.
this link is for flat oval pipe, find the one for round exh pipes instead .
Can't recall if the pipes are flat oval or round, its been 2 years and it held up fine.
https://www.amazon.com/EVIL-ENERGY-Exha ... 9hdGY&th=1
A welder is definitely in my future. I just want to get this on right now. I've done a little migraine welding in the past so hopefully I remember the most of it and my FIL can give me some better tips.
A trip to Harbor Fright for a welder might come sooner rather than later.
I did see something like this which would work a lot better if/when I can weld it on
https://www.amazon.com/FGJQEFG-Hardware ... F0aWM&th=1
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