2000 Volvo V70 XC--Check Engine Light!

[adk793]

Have it tested for sure.

You don't need to replace it until you need to pass emissions again (don't set any environmentalists loose on me).

My biggest concern is the O2 sensors. I read that if the cat. conv is bad, then it will cause the O2 sensors to go bad??

Also do i just turn off the check engine light every few days/whenever it comes on?

[jblackburn]

It's usually the other way around...if the O2 sensors go bad, they can kill the converter.

Only the rear one is affected by the cat. converter being bad, and it will just yell at you through the check engine light.

You can reset it, but you'll probably get so annoyed at it that you just end up fixing the thing. That's why I replaced my air pump.

[adk793]

Thanks for the help. Heres my next debate, is the car worth keeping despite this large/expensive repair. Selling it came to mind, but i dont know. Just i dont have the money to fix this. Ive spent soooo much on this car already. I didnt expect a volvo to be so problematic. If i do sell it, would it pass smog with this code coming up--even if i clear it?

If your recomendation is to keep the car, how should i go about the repair. Should i ignore it for 2 years until my smog test. I live in california but i was told because the car is originally from Massachusetts, i can buy a non california catalytic converter, and it would work as well and turn out to be much cheaper! how about if i buy the part from a nevada dealership, instead of california?
The guy who sold me the car 3 months ago owns a volvo dismantler company--would he be able to install me a used cat. conver...or does it have to be new?
If this job is gona cost me $900 like i once heard from my mechanic, and the car cost $6.5K,i feel screw it!
For the update, its a 2000 V70 XC AWD/SE with 96K miles.

I love volvos and this is not my first1, but ive never had SOO many problems! did i get unlucky, or is this what volvo is and its time to move on!?

[jblackburn]

There's no sense in getting rid of a good car over that, at least to me.

Get it tested before doing ANYTHING. It may just need an O2 sensor.

If you determine it does need a new converter, get an out of state emissions pass, have a used one welded to it, and exchange yours to get a core deposit back. You should be able to take care of that for only a few hundred.

Any car will throw problems at you. I owned an older Honda before my Volvo, and despite everyone's great opinion of Honda's reliability, mine was an absolute piece of junk. It was in great shape, but it broke down ALL the time. My parents have owned 2 more, and they've been completely trouble-free though.

[adk793]

I spoke with the volvo guy who sold me the car and he said that his experience with this cod/car is a faulty front oxygen sensor. I guess my best bet would be to replace that first? I heard that you need a Volvo OEM Cat conv for this car b/c otherwise things fail and go wrong. Do i need a volvo oem O2 sensor, because i got quoted $298 from the dealer which is redic! Where else can i get volvo genuine for cheaper. Or what other brands are good?? Bosch?

Being that my car is not from California, how can i get an out of state emission pass or be able to buy the parts cheaper from out of state?

[FlyingVolvo]

If it's any comfort, after I had that code several times, I had the car smog checked (live in Ca too), and it passed with well below average numbers. Don't throw a ton of money at it just yet, but having it smog checked to see what numbers come up might be a good idea.

[adk793]

Well its great to know my problem isnt very severe but my convern now is that if the O2 sensor is bad but it still passes emissions test, it will cause the Cat Conv to go bad which will then cause the car not to pass the emmisions test because of this?

Anyone have any repair instructions/advice for the front oxygen sensor?

[FlyingVolvo]

There are some write-ups on how to change it, it's not that bad of a job. You can't repair the old one though, need to replace with OEM sensors. You can get a good deal on prices online.

[850tech]

You can try replacing the rear O2S as a first step if you are not going to have the cat efficiency test done at the smog station.
In my experience (mind you, with other makes mostly) the rear O2S is the most common cause of cat efficiency codes.

That said, in response to concern of causing further damage to your car as a result of not addressing this code. In the short term, the answer is no. The cat being bad will not harm the rear O2S, it would simply read exactly the same as the front on does, which is why comparing them is the first step to diagnosis as I stated in an earlier post. Also, if it was the rear O2 that was bad, it is simply a monitor for the cat and has no effect on the fuel delivery.

Now that covers the short term, but the worst case scenario for driving around with a CEL on is something more critical failing and you having no alert to warn you (Your CEL is ALREADY on!) Now say this fault is the far more critical front O2S, and say it sticks lean, well the computer will just start to add more and more fuel thinking the O2 reading (lean) is correct and more fuel is the solution. This situation is what causes O2S related premature cat failure, the excess fuel exits the engine and ignites in the extreme temperatures within the cat melting the Palladium, Rhodium and Platinum within the cat rendering it useless, if it even remains. I've seen cats completely hollow (which means no core btw) even on relatively new cars after front O2 failure being ignored

[adk793]

Just to give an update, and see if people have any more advice, its been about 700 miles n the light is back on!I checked it and again, P0422, Cat Conv Efficiency Low (Bank 1). At first i thought the computer was tripping n the light disappeared but though its been so long, there is obviously a problem. I would prefer to spend as little money as possible, but at the same time dont want my O2 sensors to go from a bad cat. n the opposite. Should i really take it in n have it changed to help keep it running, or what! like i said, love volvo when it runs, but when it breaks, i almost wana get rid of it!