1998 V70 NA Failed Emissions High CO and HC at idle

evilxsystems · Post by **evilxsystems** » 30 Nov 2015, 14:58

Hey Guys-

I finally got around to fixing my P0172 error due to that horrible passenger-side vacuum elbow yesterday. The car is running much smoother now so I gave it a shot and took it in for the emissions test today. FAILED. High HC (HC 220 limit, 322 FAIL) and High CO (CO 1.26 limit, 7.26 FAIL). I was driving it for months with the P0172 error and it was running really rich, could it just be sludge build-up that needs to burn off or should I start trying to fix things? I'm worried I might have hosed the catalytic converter running it with the vacuum leak for so long. Is there a way to clean out the catalytic converter? What else could be causing the high HC and CO?

-Thanks
Jason

Post by **misha** » 30 Nov 2015, 15:06

Did you reset ecu after fixing vacuum leak?
Do you have any other dtc?

Post by **bmdubya1198** » 30 Nov 2015, 15:22

Have you overhauled your PCV system? That could be backing things up.

evilxsystems · Post by **evilxsystems** » 30 Nov 2015, 15:28

hmmm....nope I didn't reset the ECU. Do you think it will help? I just need to disconnect the battery correct?

evilxsystems · Post by **evilxsystems** » 30 Nov 2015, 15:30

bmdubya1198 wrote:Have you overhauled your PCV system? That could be backing things up.

What do you mean by an overhaul? All I've done so far was replace/reroute the broken vacuum line.

Thanks!

Post by **bmdubya1198** » 30 Nov 2015, 15:36

evilxsystems wrote:
bmdubya1198 wrote:Have you overhauled your PCV system? That could be backing things up.
What do you mean by an overhaul? All I've done so far was replace/reroute the broken vacuum line.

Thanks!

Did you replace the components in the PCV system? It is a series of several hoses and an oil trap. There are several symptoms associated with the system getting clogged, and increased emissions is one of them, IIRC. Search it on this forum, there is a LOT of information on it.
Resetting the ECU will also help, there is a drive cycle procedure listed on this site somewhere.

evilxsystems · Post by **evilxsystems** » 30 Nov 2015, 16:00

bmdubya1198 wrote:
evilxsystems wrote:
bmdubya1198 wrote:Have you overhauled your PCV system? That could be backing things up.
What do you mean by an overhaul? All I've done so far was replace/reroute the broken vacuum line.

Thanks!
Did you replace the components in the PCV system? It is a series of several hoses and an oil trap. There are several symptoms associated with the system getting clogged, and increased emissions is one of them, IIRC. Search it on this forum, there is a LOT of information on it.
Resetting the ECU will also help, there is a drive cycle procedure listed on this site somewhere.

Nope, haven't done that. My wife really want to drive the car now. Is there anything quick I could do that would be relatively easy (couple hours and cheap) to do rather than rebuilding the whole PCV and replacing all the vacuum lines? Could I put some SeaFoam in the PCV to flush it? If it's not too much trouble could you point me to a good thread on clogged PCVs?

-Many thanks!!!

Post by **bmdubya1198** » 30 Nov 2015, 16:02

jblackburn has a good DIY for it, which also includes lots of good information on the system. https://www.matthewsvolvosite.com/forums ... hp?t=28487

evilxsystems · Post by **evilxsystems** » 30 Nov 2015, 16:27

bmdubya1198 wrote:jblackburn has a good DIY for it, which also includes lots of good information on the system. https://www.matthewsvolvosite.com/forums ... hp?t=28487

Wow that is an awesome post, thanks! But also looks like a huge job...How hard would it be just to pull the flame trap housing

to clean it with some SeaFoam like jblackburn suggests? It's kind of buried but I was able to replace the vacuum line on it with removing it from the car. Do you think I could just run a little Seafoam through the PCV system?

Post by **bmdubya1198** » 30 Nov 2015, 17:44

I don't know if it would be the best idea to put a fuel cleaner like SeaFoam in the flame trap, but you could try it. Not sure how well it mixes with oil, even though it is suggested to be used in that manner. I just don't like putting fluids in my crankcase that aren't oil.