03 v70 non-turbo catalytic converter

Post by **Biggertuna** » 29 Mar 2020, 19:29

Hi - Think my catalytic converter needs to be replaced on my 03 v70 non-turbo automatic(B5244S,176k miles). CEL isn’t lit, but noticed a rattle during acceleration and clunk when the car turns off. Found a rubber mallet and lightly banged the cat; noticed the same rattle.

Anyway, any recommendations for an aftermarket catalytic converter? Not sure I want to pay $1400 for a genuine Volvo cat.

Post by **RickHaleParker** » 29 Mar 2020, 20:07

You can get a direct fit MagnaFlow for V70s with naturally aspirated engines for under $500.00. MagnaFlow part number 51660.

Post by **darrylrobert** » 30 Mar 2020, 04:43

are there any performance symptoms apart from the noise?...the exhaust has a joint about half way, it would be easy to get one from your local junkyard.

Post by **Biggertuna** » 30 Mar 2020, 05:59

darrylrobert wrote: ↑30 Mar 2020, 04:43 are there any performance symptoms apart from the noise?...the exhaust has a joint about half way, it would be easy to get one from your local junkyard.

Yes - I've noticed a drop in fuel economy. It's also is a bit sluggish on acceleration.

Post by **RickHaleParker** » 30 Mar 2020, 06:44

darrylrobert wrote: ↑30 Mar 2020, 04:43 it would be easy to get one from your local junkyard.

Not here in the United States where the OP and I are. It is illegal to sell a used catalytic converter with it being tested and re-certified. Nobody does it here because it is too cost prohibitive.

Post by **oragex** » 30 Mar 2020, 06:54

There are several other things to check before suspecting the catalytic converter. See the heat shield right above the exhaust manifold - behind the engine, it breaks at the securing bolts and starts rattling. The rest of the exhaust also has several aluminum heat shields that break at the securing bolts and will rattle - difficult to fix and expensive new from Volvo. The clunk when switching the engine off could be several things such as broken front or rear muffler brackets, engine mounts, etc.

Post by **SuperHerman** » 30 Mar 2020, 14:28

Before spending any money you have to eliminate other causes. Heat shields are known noise makers as well as failed exhaust suspension parts. What you describe could be either or both of these. With prudence I would position yourself safely to see the exhaust system and have some one turn off the car and watch for movement - where is the clunk. oragex is spot on here.

You can pull the O2 sensor and using a mirror and flash light examine the condition of the honeycomb cat structure for broken parts and breaks. Performance issues, if cat related, would be a clogged up cat - you would also be able to see this.

On my old XC70 I installed an Eastern Cat and had 30k trouble free miles before I sold the car. I assume it is still going strong. It was a plug and play solution. Installation was very straight forward and fit was spot on.

Post by **darrylrobert** » 31 Mar 2020, 03:15

RickHaleParker wrote: ↑30 Mar 2020, 06:44
darrylrobert wrote: ↑30 Mar 2020, 04:43 it would be easy to get one from your local junkyard.
Not here in the United States where the OP and I are. It is illegal to sell a used catalytic converter with it being tested and re-certified. Nobody does it here because it is too cost prohibitive.

interesting, i didnt know that. not here i just checked gumtree is full of used cat converters

Post by **June** » 31 Mar 2020, 10:47

SuperHerman wrote: ↑30 Mar 2020, 14:28 oragex is spot on here.

Absolutely!

You can pull the O2 sensor and using a mirror and flash light examine the condition of the honeycomb cat structure for broken parts and breaks. Performance issues, if cat related, would be a clogged up cat - you would also be able to see this.

If the honeycomb is rattling, as the chunks move they can cause a intermittent or constant blockage. I experienced many busted honeycombs from being submerged in water hot. Initially the chunks are big, as they rattle around small pieces break loose clogging the passages in remaining honeycom as well as bigger chunks can turn sideways then rattle back around causing intermittent blockages. I have looked at all converters removed from those cars. How it breaks, and the length of time driven that way seems to be the variable from what I observed. Eventually the car will pass it out the tailpipe. One of them came off empty. June

Post by **Biggertuna** » 01 Apr 2020, 12:08

Thanks for all the suggestions. Been reading that the rear O2 sensor is a pain to remove. Any recommendations on how to remove?