I own a 2004 S60, with approximately 132,000 miles. Just had the mass air flow sensor replaced and now I'm experiencing a rattling sound underneath and an icky smell from the exhaust pipe. Guy friends have said that it's definitely the catalytic converter and informed me that it's wicked expensive to replace.

Any feedback? Suggestions for the most cost effective way to replace this part?

 

Is the check engine light on? Normally for the cat to go is due to the car running rich and pushing unburnt fuel onto the cat. It could also be the O2 sensors not functioning to lean out the mixture - but that should set off the check engine light (then again - make sure the CEL bulb is working when you turn the key on before starting the car. Assuming you are not in California, a new cat costs about $400 for your car (w/o install) plus you'd want to throw in a new O2 sensor for another $100 (not sure which engine you have - it may have two O2 sensors) so I'd be concerned about knowing what caused the problem in the first place. If you drove a while with a bad MAF sensor its possible to have gummed up the cat. Do you have a loss of power or is the smell the main symptom? I'd start by seeing if the car has stored any OBD2 codes, then look at the spark plugs to see if they are wet/black looking or a grayish tan (wet/black means unburnt fuel - bad for cats). Next I'd inspect or replace the O2 sensor (it plugs into the exhaust pipe so again it should be gray not black). Finally to getting a cat installed - its just part of the exhaust pipe - has like 3-4 bolts on the front and a band clamp on the back so its a DIY project for somebody with jack stands and a moderate set of wrenches. In fact I need to drop in a new cat this weekend into my son's S40 (broken flex joint on that one - so no issues with the fuel system) It shouldn't take a shop more than 1.5-2 hours labor. Note that the $400 is what you'd pay mail order - if your local mechanic does the part ordering and install they will probably quote more like $500 to cover the handling and offer a warranty if the part is bad.

 

I have a 2004 S60 2.4 non turbo. A mechanic said that I needed the 2 catalytic converters when I brought it in to diagnose why the check engine light was on. I sprayed Mass Air Flow sensor cleaner, but continue to get codes P0420, P2227, and P0108. Any suggestions?

 

P0420 says Catalyst System Efficiency Below Threshold (Bank 1). Change the cat.

P0108 and P2227 and both MAP (Manifold Air Pressure) sensor problem. No amount of spray to the MAF (Mass Air Flow) sensor is going to help.


Either get a second opinion or sell the car.

 

I think I will be looking at fixing it. Does replacing the catalytic converters sound right considering those codes in your opinion?

 

The codes tell you where to start looking, it doesn't necessary tell you what's broken.
There are test procedure to test the catalytic converters, one is test the tail pipe emission and one is test the temperature before and after the cat. Both require special tools, so I'd pay a shop that knows what they're doing.

 

Sounds good. Thank you.

 

Are Federal and California catalytic converters interchangeable? I've been given mixed reviews. I've been told that they are interchangeable, but that it wouldn't pass the emissions in CA or NY, but would be fine anyplace else. Another mechanic told me that if I put a Fed cat on a vehicle that was initially a CA cat vehicle, that would destroy the exhaust sysyem. The Volvo dealership said they are interchangeable.

 

If you live in CA or NY, put in a CA cat.

Otherwise, put in a Federal cat.

 

Hi there!

I have a Volvo S60 (turbo) from 2005.

The story goes like this. My Volvo almost all the time had an engine light on (I bought it this way), but was told it might be just a sensor. Mechanics would reset it when I had to get it inspected.

So,
1) I am driving as an UberEats delivery person and after driving my Volvo for about 5,000 miles I thought I was hearing a noise like something automated (like a squeak) right when I drive it at slow speed.
2) Took the car to a mechanic; he checked for the noise but was not able to confirm anything wrong. He did not hear it. He changed the air filter and added some oil. He also found some codes such as 140C, 140D, 120D, and 400C. Told me there might be something about the catalytic converters but that is too soon to tell.
3) A few days later the maintenance message came to my dashboard. The mechanic changed the oil, oil filter.
4) Next day I drove the car many miles. Then the day after the dashboard said "reduced engine performance" and stopped running. I was able to drive it to the mechanic shop then she stopped.
5) He told me the throttle body needs to be replaced. We replaced it with a used one so I can save money. The engine light was on again and it showed a catalytic converter code.
6) Took it to AutoZone to read the engine light and they said it is a code for the catalytic converter. I just needed to double-check.
7) Went back to my mechanic and he told me to buy this special additive to add to the fuel tank to "clean" the converters. He took out the engine light to see if it comes back after I drive it with this additive inside the fuel tank. If the engine light came back, I would return to him. He also said that with Volvo's it takes a few tries to diagnose a problem, hence the additive and taking out the light a few times to see if it comes back.
8) Engine light came back on and the codes were air mass flow and catalytic converter. This happened twice (these two codes I mean).
9) Today he told me to change the air mass flow.

What do you all think? Is there a connection between air mass flow and a catalytic converter? What about the throttle body in connection to the catalytic converter? What other options do I have to make sure it is not the catalytic converter? What other tests can he do on her to rule out the converter? Can it be the air mass flow piece? Also, how much is this piece?

Thanks for your help.

 

Do you understand what a catalytic converter is? It's a ceramic honeycomb (mounted in that muffler looking device under your car) coated with platinum, rhodium and paladium (sp) that when working correctly converts CO and HC into CO2 and H2O. The rear section deals with NO (nitrous oxide) but I forgot the chemical reaction.

So - do you live in an area that Emission inspections are required to register your car? Does the car run bad? If not ignore it - and drive it. If you have any extra money (after food clothing shelter, etc) maybe try to solve the check engine light if it really bothers you. It does seem like every cab I got into ( a few years ago) had the check engine light on. Those drivers were not worried about it.

 

Sir,

I am a female who has no mechanic knowledge. So to answer your question, NOOOOO! You can also just answer like a gentleman without the extra noise in the background like we all should know car mechanics!!

Thanks, no thanks, for the non-advice. BYE!

 

Sorry did not mean to upset you, my question was - do you live in an area that Emission inspections are required to register your car? Does the car run bad? If not ignore it - and drive it.

I was just trying to offer a free solution.

 

Thank you for getting back to me and for the apology. Yes, I live in DE, and emissions are included in the inspection. The only time the car did not run was connected to the throttle (which I replaced). Since then she stopped on me once (after I started it). Hence, the extra investigation on trying to figure out if the converters need replacement, or something else.

Thanks again for the reply. Good night.