Help! Catalytic converter replacement

[XLRJIM]

Engine check light came on, checked codes and got P0420, Catalytic Converter low efficiency. Reset the code and have been driving for couple days with out light coming back on. Mechanic suggests that since I do a lot of very short trips to get it out on the road and really get the system heated up, but he cautioned that may not fix the problem. Replacing the Cat with a OEM requires replacing the manifold and doing that requires pulling the engine. Estimated work time 16 hours plus about a 800 dollar item.

Has anyone replaced the cats with welded in universal ones, and is there even room to do it?
Any suggestions would be appreciated.

Thanks JIM

 

[AL_Jazz]

...pulling the engine to replace the cats?

 

[GizmoQ]

Engine check light came on, checked codes and got P0420, Catalytic Converter low efficiency. Reset the code and have been driving for couple days with out light coming back on. Mechanic suggests that since I do a lot of very short trips to get it out on the road and really get the system heated up, but he cautioned that may not fix the problem. Replacing the Cat with a OEM requires replacing the manifold and doing that requires pulling the engine. Estimated work time 16 hours plus about a 800 dollar item.

Has anyone replaced the cats with welded in universal ones, and is there even room to do it?
Any suggestions would be appreciated.

Thanks JIM

Wow, your mechanic sounds like a dealership service writer. Yes, you can get the manifolds out without removing the engine - I've done a few times.

To save yourself some money, you can have someone with HP Tuners turn off the rear sensors, then get a skilled exhaust specialist to cut a rectangle in the bottom of the cats, gut them, weld the piece back on - total cost ~$400; time 2-4 hours; nothing but guts removed.

 

[gamblingman]

Would a certified shop be willing to make such a "repair"?? Would the rear sensor need to be turned off permanently, even after the "repair"? My car is setting off the same code.

 

[GizmoQ]

Would a certified shop be willing to make such a "repair"?? Would the rear sensor need to be turned off permanently, even after the "repair"? My car is setting off the same code.

Probably not. Yes.

 

[Jergig1955@gmail.com]

I have the same problem on my 2009 XLR. I am told that the cat is in the manifold is that correct ? Would it still be possible to gut the cat if it is in the manifold ?
By turning off the rear sensors is that the same as disconnecting them ? Also if this is done and the cat is gutted will the chk engine light stay off and will it pass an emissions test ?
g

 

[V Happy]

Jergig
I had the same problem with my 2006 v this summer. I did find out you don't have to pull the engine to replace the manifold cat. My independent shop changed it in about five hrs and the part was under $900.00. I did find out there is aftermarket headers available from magnaflow. One guy on here replaced both of his with the aftermarket magniflows and had great success. There is also a tread on here where they ran Mr gasket cat cleaner thru the car and it fixed the problem. In my case that only made the problem worse. I have the old manifold and there appears,to be something rattling around in it. When I get two working hands I'm going to cut it open for inspection. I thing I did notice in Researching this is that it is always the passengers side that goes bad. I think when all was said and done I had under 1400 in the whole job. I'm happy and the V is running perfect.
V Happy
PS If you are interested pm me and I can get you the place I ordered mine. It beat everyone by 100 bucks and freight was cheap.

 

[Jergig1955@gmail.com]

[FONT=&quot]Thank you for the info. I too came across aftermarket headers at a real good price. An internet store called auto anything havs both sides for a little over $800. Magnaflow name brand with a ceramic coating on the inside. My XLR is a 2009 and the local Cadillac dealership explained that there is a 8 year 80,000mi emissions warranty that I am just under . If nothing adverse caused the converter to go bad it should be covered, parts and labor. We will know today. My guess is that they will only cover the one side and It would be smart to do both. [/FONT][FONT=&quot]FYI, the dealership gave a quote of over $5000. [/FONT]

 

[Lineaire]

Need to replace catalytic converter on a V

Hello!

I too need to replace one of the catalytic converters on my 2008 XLR-V.

My Cadillac dealer is asking about $ 4,000 Canadian dollars to change it...

I asked my local mechanic shop and they are not sure they can replace the manifold without removing the engine.

Next week, I will show the car to an exhaust specialist in Montreal.

Any advice would be appreciated, I think it's a shame to charge that much money for a design flaw.

 

[V Happy]

Catalytic converter replacement.

Laniere
Pulling the engine is crazy. Cadillac says that but I had mine replaced and if I remember correctly it required 5 hr labor. If you look back and search it a few guy on here did it off a creeper in there own garage. I had mine done about two years ago (passengers side) I ordered the part from Rinker in Michigan. The after markets fit well also I think they are Magnaflow. Good mechanic with a lift should have no problem doing this.
V Happy

 

[Lineaire]

Lineaire
Pulling the engine is crazy. Cadillac says that but I had mine replaced and if I remember correctly it required 5 hr labor. If you look back and search it a few guy on here did it off a creeper in there own garage. I had mine done about two years ago (passengers side) I ordered the part from Rinker in Michigan. The after markets fit well also I think they are Magnaflow. Good mechanic with a lift should have no problem doing this.
V Happy

Thanks for your reply! It make feel a bit better!

I will let everyone know how it turn!

 

[Glenn Thompson]

Cats can be replaced with aftermarket ones

I too had the low efficiency cat code set on the wife's 05 XLR with 130,00 on it. Took it to my local muffler shop and asked about welding on new cats directly to the cast iron manifolds. I too researched the new OEM cats as well as the Magnafolw headers but decided to try aftermarket because of the price of them and extra labor involved. He said he'd give it a try so I let him. Went well, he was able to cut off the old cats from the manifolds and weld on new cats (without removing thee manifolds). No issues since and passed California emissions test just recently so all is good. Total cast was about $800 including the new cats (I did both while I was at it) So yes it can be done fairly cheap.
Glenn Thompson

 

[ljkrenek]

CAT replacement

I think after reading all the responses I would go the way of the header modification. Kinda like a no brainer.......more HP/torque and efficiency for not a whole lot more money.

 

[David_B]

I think after reading all the responses I would go the way of the header modification. Kinda like a no brainer.......more HP/torque and efficiency for not a whole lot more money.

Be careful, Magnaflow will try to sell you the wrong right manifold/cat.

If you get one that fits come back and tell us what model fits your 2005. after trying 2 different ones they told me that they don't sell one that fits my 2004.

The head changed in 2006, so they take a different manifold that 2004/5.

 

[gamblingman]

Took mine to a muffler shop. He ordered a generic one (said that it might not fit) I went to see him today and he showed me the cats up on the lift. They are very small cats, almost square (MUCH smaller than the cat he ordered) Why would it be a problem to cut one of them out and replace it??
I hope he's a qualified shop and looking at the right portion of the exhaust, because there is no way those take 30 minutes to cut out and weld back in? Am I or he missing something here?
Also does anyone have a part number of one that will work? Thanks in advance

 

[long Tall Sally]

the 30 minutes was not a replacemnt but cutting a hole in the cat to gut it and weld it back up. It is a bigger job to replace than that

 

[willys46]

My 2005 has a P0430 code, bank 2 low efficiency.
Has anyone tried the BOSAL replacement manifold/converter on a 2005?
The picture of their CARB compliant unit looks the same as the MagnaFlow replacements.
Are the MagnaFlows easier or harder to re-install than the OEM.
I going to try replacing the left side without dropping the engine. It looks like removing the oil filter and it's extension might give enough space to tip out the old manifold on the left side.
Does anybody who has changed them without dropping the engine have any tips.
I couldn't find a local shop that would cut off the old and weld on a new converter.

 

[richardyoo]

Does anybody who has changed them without dropping the engine have any tips.
I couldn't find a local shop that would cut off the old and weld on a new converter.

I've removed mine on jack stands in my driveway and installed headers.... it can be done... it will take awhile and you will be sore afterwards... but it can be done. I think it took me 4 or 5 hours just for one side.

I've actually done it twice, the 2nd time I pulled the headers out to wrap them in heat wrapping... again, on my back with the car on jackstands in my driveway.

The passenger side is more difficult than the driver side due to all the AC compressor lines and such.

 

[IAN]

Cat. converter

willys46

A motor with a poor combution,( low octane ? ) means that more debris are to be exhausted and going into the converter.

Having an after market converter installed is not ideal, as it could not communicate properly with the motor module.

Its my opinion, good luck

IAN

 

[JohnnyBfromPeoria]

I'd try replacing the rear oxygen sensors, as those are what is telling the computer the catalytic converters are not functioning correctly. I'd probably also install spark plug anti-foulers on both sensors while re-installing. This spaces the sensors further back, off the exhaust flow, so they are less sensitive. But, I'm an outlier, a rebel. You don't want to get mixed up in my nonsense.

John B.