Rusted through cat, replacement suggestions [solved]
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Rusted through cat, replacement suggestions [solved]
Hi all, 2003 EX sedan, 126k. No cel or codes. Catalytic converter is rusted through and leaking badly, causing O2 issues.
I will diy but I'm new to Civic repairs and if aftermarket parts will be ok.
Suggestions on cat brand and will lower priced cats be ok for ct emissions or smog testing?
I'm all for oem but will prefer to spend less on this 22 yr old civic.
I will diy but I'm new to Civic repairs and if aftermarket parts will be ok.
Suggestions on cat brand and will lower priced cats be ok for ct emissions or smog testing?
I'm all for oem but will prefer to spend less on this 22 yr old civic.
Joined: Aug 2003
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From: Las Vegas, NV
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re: Rusted through cat, replacement suggestions [solved]
Magnaflow has a 49-state legal for like $550 (OEM is like $1500 new): https://www.magnaflow.com/products/4...onverter-49483
and one slightly cheaper that's "HM grade" (whatever that means) for $525: https://www.magnaflow.com/products/9...onverter-93228
it's a full downpipe replacement, so you're looking at 2 bolts (with springs and a doughnut gasket) where it mates to the exhaust mani and 3 bolts/nuts where it mates to the midpipe (with a regular flat gasket). Considering your cat is rusted out and leaking, the latter 3 bolts are probably going to be a pain to remove. It's made with stainless steel, so there's that.
Back in the day, I'd 100% vouch for the Random Technology cat (ran one in my 2002), but company went defunct a while ago. That passed NV smog without issue (just OBD readings), and it was a high flow performance cat. I'd imagine magnaflow should pass smog just fine
Here's a universal option for $200 if there's enough pipe to cut out the old one and weld in a new piece: https://www.magnaflow.com/products/5...onverter-51355
Though I'd honestly spend the extra money and go with the drop in replacement if I were you.
and one slightly cheaper that's "HM grade" (whatever that means) for $525: https://www.magnaflow.com/products/9...onverter-93228
it's a full downpipe replacement, so you're looking at 2 bolts (with springs and a doughnut gasket) where it mates to the exhaust mani and 3 bolts/nuts where it mates to the midpipe (with a regular flat gasket). Considering your cat is rusted out and leaking, the latter 3 bolts are probably going to be a pain to remove. It's made with stainless steel, so there's that.
Back in the day, I'd 100% vouch for the Random Technology cat (ran one in my 2002), but company went defunct a while ago. That passed NV smog without issue (just OBD readings), and it was a high flow performance cat. I'd imagine magnaflow should pass smog just fine
Here's a universal option for $200 if there's enough pipe to cut out the old one and weld in a new piece: https://www.magnaflow.com/products/5...onverter-51355
Though I'd honestly spend the extra money and go with the drop in replacement if I were you.
Last edited by xRiCeBoYx; Dec 18, 2024 at 03:22 PM.
Thread Starter
Registered!!
Joined: Jun 2021
Posts: 19
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From: northeast USA
Rep Power: 0 re: Rusted through cat, replacement suggestions [solved]
Magnaflow has a 49-state legal for like $550 (OEM is like $1500 new): https://www.magnaflow.com/products/4...onverter-49483
and one slightly cheaper that's "HM grade" (whatever that means) for $525: https://www.magnaflow.com/products/9...onverter-93228
it's a full downpipe replacement, so you're looking at 2 bolts (with springs and a doughnut gasket) where it mates to the exhaust mani and 3 bolts/nuts where it mates to the midpipe (with a regular flat gasket). Considering your cat is rusted out and leaking, the latter 3 bolts are probably going to be a pain to remove. It's made with stainless steel, so there's that.
Back in the day, I'd 100% vouch for the Random Technology cat (ran one in my 2002), but company went defunct a while ago. That passed NV smog without issue (just OBD readings), and it was a high flow performance cat. I'd imagine magnaflow should pass smog just fine
Here's a universal option for $200 if there's enough pipe to cut out the old one and weld in a new piece: https://www.magnaflow.com/products/5...onverter-51355
Though I'd honestly spend the extra money and go with the drop in replacement if I were you.
and one slightly cheaper that's "HM grade" (whatever that means) for $525: https://www.magnaflow.com/products/9...onverter-93228
it's a full downpipe replacement, so you're looking at 2 bolts (with springs and a doughnut gasket) where it mates to the exhaust mani and 3 bolts/nuts where it mates to the midpipe (with a regular flat gasket). Considering your cat is rusted out and leaking, the latter 3 bolts are probably going to be a pain to remove. It's made with stainless steel, so there's that.
Back in the day, I'd 100% vouch for the Random Technology cat (ran one in my 2002), but company went defunct a while ago. That passed NV smog without issue (just OBD readings), and it was a high flow performance cat. I'd imagine magnaflow should pass smog just fine
Here's a universal option for $200 if there's enough pipe to cut out the old one and weld in a new piece: https://www.magnaflow.com/products/5...onverter-51355
Though I'd honestly spend the extra money and go with the drop in replacement if I were you.
Joined: Aug 2003
Posts: 21,620
Likes: 1,252
From: Las Vegas, NV
Rep Power: 511 re: Rusted through cat, replacement suggestions [solved]
^^ also a viable solution, but potentially temporary given the fact that it's already rusted through. Welding would increase the likelihood of corrosion at the weld sites, purely by the nature of how welding affects metal crystalline structures. If you don't plan on keeping it long, the patch fix at a muffler shop wouldn't be a bad idea. If you're looking to run that car into the ground, spring for the stainless downpipe.
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Update, thanks for all replys.
I got into a deeper look at the exhaust leak at the cat and discovered it was rusted through underneath the 4 heatshield brackets which are welded onto the cat. The brackets are still pretty solidly attached even with small holes under each one. I used the JB Weld high temp paste and filled/ molded a patch on each. It is quieter for sure and Ill check for leaks after some miles driven. Ill update after my Ct emissions test next week.
I got into a deeper look at the exhaust leak at the cat and discovered it was rusted through underneath the 4 heatshield brackets which are welded onto the cat. The brackets are still pretty solidly attached even with small holes under each one. I used the JB Weld high temp paste and filled/ molded a patch on each. It is quieter for sure and Ill check for leaks after some miles driven. Ill update after my Ct emissions test next week.
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