Direct fit catalytic converter install ?

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The catalytic converter on the Grand Prix needs to be replaced. Being a 2006 model year and being in CA, there are limited offerings and Magnaflow is the only option for a direct fit CARB compliant cat con. I figure it will be cheaper to spend $500 on the direct fit part and install it myself than have a shop purchase and install a CARB compliant universal unit (which run $250+ online). Are there any tricks to getting the old converter and exhaust pipe assembly off or the new one on? The vehicle has 150k+ miles on it and spent its early years in the Midwest, so I am hoping stuck bolts and rust at the flange joints are not issues.

Also, with a self install, how do I dispose of the old unit? I have heard that they cannot be recycled at public scrap yards in order to deter theft, but they have value because of the precious metals.
 
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Check out Eastern Catalytic Direct-fit Converters. I hear some of these GM models are picky about cheaper direct fits than Eastern. My Century had a direct fit from a shop put in 40k ago and its bad again. Someone told me i needed a high wash cat, not sure if this is true or applicable to you, but you might want to research your model thoroughly to see if they are having problems with oem replacements or cheaper. Sometimes a specialty aftermarket piece is needed to fix the issue.
 
Originally Posted By: 901Memphis
Check out Eastern Catalytic Direct-fit Converters. I hear some of these GM models are picky about cheaper direct fits than Eastern. My Century had a direct fit from a shop put in 40k ago and its bad again. Someone told me i needed a high wash cat, not sure if this is true or applicable to you, but you might want to research your model thoroughly to see if they are having problems with oem replacements or cheaper. Sometimes a specialty aftermarket piece is needed to fix the issue.

No dice on Eastern. Magnaflow is my only direct fit option.
 
Well, if that's your only option, I guess you are stuck trying it unless you want to have a shop weld in correctly sized universals.

I had a bad experieince with a Magnaflow direct fit y-pipe on my truck. Turns out they had apparently designed it to fit manual transmission trucks, not automatics. It would not clear the shift cable on my truck at all, and rubbed on the frame, which I imagine would be an issue even on a manual transmission truck. There was simply no way to bolt it up to the truck. Overall construction was beautiful, it was just a poor fit.

I returned it, and got a Walker, which dropped right in perfectly.

I didn't have any issues getting the old y-pipe off, but I did use air tools and the truck has been in the south all of its life. I would liberally soak the nuts/bolts in PB Blaster or similar and let it sit before trying to remove them...might prevent headaches later. I chanced it and reused my old gaskets, but you may want to order new ones to play it safe. New gaskets are not supplied with the cats with any manufacturer I know of. Whether or not they need replacement depends on the design of the flange on your vehicle.

Also, get the car as high off the ground as possible. Replacing bolt up sections of exhaust involves some finagling as the hangers only have so much play in them.

Scrap yards do take cats, but you need to provide proof of ownership. At the yard I took my y-pipe to, that means either a receipt for the new cat, a repair invoice for the cat, or bringing the car with you so they can visually check to see if a new cat has been installed.
 
Make sure you check the sticker under the hood !

The numbers on the catalytic converter have to match the sticker !

They'll look something like this:

YGMXV03.8044
YGMXR0133910
 
ya he can only purchase and install a specific cat here in cali. imo id take it to a muffler shop,i hate laying under a car while dirt and metal shavings are falling into my eyes. exhaust work is the one thing that ill gladly pay to have done
 
I might get a cheap universal cat, gut the old one, and put its housing around the cheapie. Then again...bureaucrats telling me how to fix my car tick me off!
 
Go to a special scrap metal dealer. They know what kind of cat you have, how much valuable metal is in it, the price to extract that metal, and pay you based on those factors. It really amazed me when a guy like that came to a place I worked. He could tell just by looking what car the cats came from, even though the ones we had were plain looking OEM units without markings.
 
Other than purchasing a CARB compliant part, how much more strict is it?

Originally Posted By: Merkava_4
You guys don't realize how strict it is here in California. If the numbers don't match, it's an automatic fail.
 
Originally Posted By: kschachn
Other than purchasing a CARB compliant part, how much more strict is it?


It has to be CARB compliant AND numbers matching.
 
You might try cleaning the converter before breaking your wallet. Solution of citric acid and oxalic acid. I've not tried it myself, though.

http://www.bobistheoilguy.com/forums/ubbthreads.php/topics/3391904/Re:_Fixing_Bad_Catalytic_Conve#Post3391904
 
people in other states dont know what we go through with the smog stuff. we cant just buy a universal cat for $99 and slap it on. the 3 cats on my jeep are $2400 my cost.

part of the smog test is checking to see if the cat is for that car. and hope you dont get on the high emitter or gross poluter list. ca will find a way to force you to get rid of the car.
 
Originally Posted By: Merkava_4
Originally Posted By: kschachn
Other than purchasing a CARB compliant part, how much more strict is it?


It has to be CARB compliant AND numbers matching.

I just checked and numbers match.
 
Instead of doing it yourself you might want to call Mike's Muffler in El Monte. He is reputable. His # is 626 443 5139. If you are in Corona he is not that far from you, and he can do stuff on appointments. Describe your issues to him.
 
Originally Posted By: Merkava_4
Make sure you check the sticker under the hood !

The numbers on the catalytic converter have to match the sticker !

They'll look something like this:

YGMXV03.8044
YGMXR0133910



Is the "sticker under the hood" the VIN ?
 
Originally Posted By: Skid
You might try cleaning the converter before breaking your wallet. Solution of citric acid and oxalic acid. I've not tried it myself, though.

http://www.bobistheoilguy.com/forums/ubbthreads.php/topics/3391904/Re:_Fixing_Bad_Catalytic_Conve#Post3391904

Unfortunately, the cat isn't "poisoned" (did I just type that?!?), so cleaning will not help. It is actually breaking up internally, causing a rattle at certain rpm/engine load. Apparently, this is an issue GM had on some cats, some of which even collapse and block nearly all exhaust flow, leading them to extend the warranties, but I am past the mileage. No codes yet, but I can feel that it is down on power at times and would like to replace it before a catastrophic failure.
 
Originally Posted By: Cristobal
Is the "sticker under the hood" the VIN ?

No, it is an emissions sticker that lists the engine family and states which emissions standard(s) the vehicle meets, such as Federal, California, LEV (low emissions vehicle), ULEV, etc.
 
Originally Posted By: NMBurb02
Originally Posted By: Cristobal
Is the "sticker under the hood" the VIN ?

No, it is an emissions sticker that lists the engine family and states which emissions standard(s) the vehicle meets, such as Federal, California, LEV (low emissions vehicle), ULEV, etc.


I was just wondering if it goes back to 1996 cars as well. My car was in an accident and once had some front end body work done. I hope it is still there. Where is it usually affixed?
 
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