Catalytic converter and rotor question

Haasdaddy18

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Proteg5
I have an 03 MP5 and the cat is all broken up I pulled it all out will the car run ok without replaceing or do I need to order a new one, second the rotor will not come off is there something I'm missing to get it off I have removed the axles because I pulled to motor?
 
I have an 03 MP5 and the cat is all broken up I pulled it all out will the car run ok without replaceing or do I need to order a new one, second the rotor will not come off is there something I'm missing to get it off I have removed the axles because I pulled to motor?
Well, if you run an empty ( or gutted ) cat you will likely throw a CEL. You need to add a CEL fix which is a spacer that moves the O2 sensor back about a half an inch ( $20 bolt on fix ), upside is it will feel a bit sportier as a gutted cat is similar to crappy headers. As for the rotor, get a sledge and hammer it off. You could hit it with penetrating oil and try to baby it but likely rust has it firmly seated and since you are replacing it a hammer is your tool.
 
Many times there is a threaded hole in the hub area of the rotor, take a 12mm bolt and thread it in, the bolt will push the rotor off the hub.
 
Forget the CEL fix. Have someone tune your ECU for a cat delete, you will get a healthy power increase and the car will run better.

If you dont want to tune your ECU, youre best off getting a new cat. You said you pulled the motor? What? You can just cut out the car from underneath the car and easily weld in a new straight pipe, unless the cat is inside the manifold. Then you just need to take the exhaust manifold off I think.

Is your car running okay? I would also scan for codes to make sure you dont have a misfire, lean condition ETC.
 
Give the rotor a whack with a rubber mallet. It's most likely just stuck on there with a little corrosion.

As for the cat, I just bought one off of ebay. It fit great and I passed smog with flying colors.

I have an MSP, but here's the cat I bought. It was surprisingly nice. Mandrel bent, bolted right up, and my car sounds nice and mellow.
https://www.ebay.com (commissions earned)

I'm sure they either have one or can make one for your Protege. Do it right and do it once.
 
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Do it right and do it once.

Yeah, what he said.

Odds are you won't find a cat at the wreakers either, pick and pull won't sell them even in you find one, remove it and stare at the counter attendant like they had two heads. ( Trust me, I found one in a 626 and pulled it for no sale ).

When my cat dusted I found headers for $50 ( eBay special ) vs $300 for the cat.
 
Yeah, what he said.

Odds are you won't find a cat at the wreakers either, pick and pull won't sell them even in you find one, remove it and stare at the counter attendant like they had two heads. ( Trust me, I found one in a 626 and pulled it for no sale ).

When my cat dusted I found headers for $50 ( eBay special ) vs $300 for the cat.

Some reasonable quality headers is probably your best bet. If they are catless, you will need an ECU tune for the car to run optimally and make the most out of the power gains. Removing the cat will make the turbo breathe better, spool faster, cause less turbo wear (in theory) etc. I would strongly suggest placing another resonator somewhere on your exhaust system, preferably underneath the rear seats and a good quality muffler for a nice sound and lots of turbo spool.

If youre not getting an ECU tune, buy a high flow cat.
 
Some reasonable quality headers is probably your best bet. If they are catless, you will need an ECU tune for the car to run optimally and make the most out of the power gains. Removing the cat will make the turbo breathe better, spool faster, cause less turbo wear (in theory) etc. I would strongly suggest placing another resonator somewhere on your exhaust system, preferably underneath the rear seats and a good quality muffler for a nice sound and lots of turbo spool.

If you’re not getting an ECU tune, buy a high flow cat.

There's no turbo on a P5, and to my knowledge there isn't anyone that can tune a stock PCM.
 
There's no turbo on a P5, and to my knowledge there isn't anyone that can tune a stock PCM.

Why was I under the impression that this guy has a Mazdaspeed protege? Lol my mistake.

No one is able to tune this ECU? Im sure youd be able to find someone.
 
Forget the CEL fix. Have someone tune your ECU for a cat delete, you will get a healthy power increase and the car will run better.

If you dont want to tune your ECU, youre best off getting a new cat. You said you pulled the motor? What? You can just cut out the car from underneath the car and easily weld in a new straight pipe, unless the cat is inside the manifold. Then you just need to take the exhaust manifold off I think.

Is your car running okay? I would also scan for codes to make sure you dont have a misfire, lean condition ETC.
There are no Protege ECU tuning solutions, not even for the MSP; only piggybacks or standalones. The O2 sensor spacer is the only way to remove a cat and not get a CEL.
 
Thanks I got the rotors off just took a lot of on blast, as far as the motor I pulled it because the previous owner spun a bearing and I picked up a 120000 mile motor for $400 off craigslist. It didn't have the cat and mine was in pieces in the motor I pulled. I don't really want to have it tuned I'm not looking for gains just a clean daily. The body is perfect!!!!! Flawless.
 
... The O2 sensor spacer is the only way to remove a cat and not get a CEL.

There's an electronic version too...

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