Replacing CAT on '04 4.2
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Replacing CAT on '04 4.2
basically what i want to know is this a driveway job or do i HAVE to get it on a lift? i've had a hard time tracking down info on the net on multiple forums about it. a guy did my timing belt and said in order to do it, he would have to drop the back of the engine for an additional $1000 in labor!!! it doesn't look anywhere that complicated in the bentleys. looking for real life experience and tips. want to know if its worth it, or just paying midas, muffler shop, or trying to pay a dealer tech on the side.
thanks
thanks
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Yep. Been there, done that.... Downpipes (which have the pre-cat and main-cats welded inline) are one-piece and can be removed without lowering engine. BUT, a lift is probably a MUST... Can't imagine the downpipe coming out from under the car while it's on the ground!!! Exaust manifold/downpipe bolts are a sum'bitch to get at. Install the new upper O2 sensors in new downpipes, then install the new downpipes/cat assembly. Lower O2 sensors are much easier to access.
This task is not for the novice DIY'r with limited tools, experience or aptitude... But it can be done!
Lots of chatter about splicing in aftermarket cats... Lots of issues with engine/emmision codes associated with doing so. I used new oem cats/downpipes and O2 sensors. No issues or codes and a perfect fit.
If I recall, new OEM cats/downpipes are about $1300+ per side... OEM O2's will run about $600 for the set of 4. Expect to pay an indy shop $500-$700 for labor.
Good luck!
This task is not for the novice DIY'r with limited tools, experience or aptitude... But it can be done!
Lots of chatter about splicing in aftermarket cats... Lots of issues with engine/emmision codes associated with doing so. I used new oem cats/downpipes and O2 sensors. No issues or codes and a perfect fit.
If I recall, new OEM cats/downpipes are about $1300+ per side... OEM O2's will run about $600 for the set of 4. Expect to pay an indy shop $500-$700 for labor.
Good luck!
Thread Starter
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thanks for the reply.
i was considering doing this job on jackstands, but i wasn't sure if it would be high enough. i may just have to pay someone. i already got the aftermarket downpipe/cats, so thats that, but i couldn't believe it would be this much in labor costs. i guess you've verified it. the bentleys make it look very simple. i'm not worried about the tools. my only problem would be height and patience, but as long as i know it can be done...
its on the pass side if that makes any difference as i've read the drivers side can be a real pain.
i was considering doing this job on jackstands, but i wasn't sure if it would be high enough. i may just have to pay someone. i already got the aftermarket downpipe/cats, so thats that, but i couldn't believe it would be this much in labor costs. i guess you've verified it. the bentleys make it look very simple. i'm not worried about the tools. my only problem would be height and patience, but as long as i know it can be done...
its on the pass side if that makes any difference as i've read the drivers side can be a real pain.
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Audiworld Junior Member
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From: Chicago
This job is a PITA, i have attempted to replace the pass side on my 4.2 three times before giving up.
The farthest I got was had the bottom nuts loose, and couldn't get at the top nut nor remove the O2 sensor.
The farthest I got was had the bottom nuts loose, and couldn't get at the top nut nor remove the O2 sensor.
Thread Starter
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i won't lie, sounds pretty discouraging. and with that level of difficulty now i'm not sure i want midas or just any old exhaust shop working on it. they may get frustrated and break stuff up. i'll try to catch a tech at the dealer. sometimes they do work on the side. i got 3 other vehicles and dont want to get way stressed over it.
unless sloopjohnb want to do a tech session. i believe he's in MD too.
unless sloopjohnb want to do a tech session. i believe he's in MD too.
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how much did you get charged for the labor when you took it in?
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From: Olney, MD
Yeah...I'm in MD. But I hate exhaust work....last one I had done on my 02S6.
You might look for a good independent Audi tech...I don't know of one (that's not to say there aren't several!) near me; I generally do things myself or have Tischer Audi in Laurel do it. Derrick is the head technician there and he's a gem.
You might look for a good independent Audi tech...I don't know of one (that's not to say there aren't several!) near me; I generally do things myself or have Tischer Audi in Laurel do it. Derrick is the head technician there and he's a gem.
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From: Chicago
I haven't taken it in yet, since I have a factory fit part I'm thinking about having an exhaust shop just weld in the new factory size cat and leave the existing pipe.
Ive heard some quotes around $4-500 labor
Ive heard some quotes around $4-500 labor