2008 Passenger side cat removal

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2008 Passenger side cat removal

Postby HazmatikNC » Wed Nov 03, 2021 2:46 pm

I need to replace my passenger side cat on my 2008 Pathy, but I'm struggling with just getting access to the bolts to remove the old one. The Haynes repair manual says to remove the exhaust manifold heat shield which I tried to do (breaking two of the 10mm bolts that held it on along the way) but once I got it unbolted it seems to just be trapped in where it is. It looks like to get the heat shield out I'll need to get the cat off. Did they really engineer something that to remove one thing requires removal of something else that requires removal of the first thing you are trying to remove?

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Re: 2008 Passenger side cat removal

Postby smj999smj » Sun Nov 14, 2021 9:45 pm

If you want to save the manifold heat shield and reinstall it on a V6 R51, you have to unbolt the motor mount and raise up the passenger side of the engine to get it out in one piece. Broken bolts are not uncommon; they should have used 8MM bolts instead of 6MM. What many do is leave on the manifold heat shield and trim away the bottom to provide access to the bolts. You access the bolt through the passenger side wheel well with the plastic liner removed and one is accessible from underneath the vehicle. When I replaced mine, I also replaced the exhaust manifolds with Doug Thorley headers. For that, I just cut the heat shield into pieces and discarded them since the headers don't use them.

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Re: 2008 Passenger side cat removal

Postby TooMuchControl » Mon Nov 15, 2021 4:42 am

Agreed on this!

I used aviation snips to cut two slots, about two inches apart, horizontally, at the bolts. Don't be a ballerina, just get in there and cut that sucker any way you can.

This allows you to partially bend that part of the heat shield away (to be bent back later).

You don't need much access to get to the cat bolts, I found that they come off reasonably if these are factory.

I've seen a video (and a good tip) with a guy that uses a drill bit to drill out the broken studs, just enough to put in small self tapping screws that will hold the shield in place.

@ 1:09:40 of the video

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Re: 2008 Passenger side cat removal

Postby HazmatikNC » Thu Nov 18, 2021 7:18 am

I ended up replacing both passenger side cats, when I removed the downstream cat to take out the upstream cat pieces of it were falling out and I couldn't tell if it was from the upstream cat that was definitely broken or the downstream one. The heat shield I just tightened the one bolt left down really tight and I haven't heard a rattle yet. I did have to replace the downstream oxygen sensor because the threads got mangled, but the upstream sensor I kept, now at cold starts I'm sometimes getting a misfire that goes away either after a few minutes or sometimes just turning it off and on again. Is this just due to the computer getting used to the new cats? Only one time did it throw a P0301 code before it smoothed out.

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