Failed MOT, high CO

[Robert986]

Ok, first we look at the AOS..

I did the oil-cap-test.

It really felt easy to open the oil cap, no powerful vacuum at all, but I realize this is totally subjective since I have no vacuum meter.


I then went on and popped the plenum & throttle body. I must say, there is some oil in there, but is it normal levels? As you see my finger get quite soaked when I scrape the inside of the plenum, I don´t see a lot of oil in the actual manifold. at least not a lake.. ;-)

So, does this mean that my AOS is not up to the job? Should I change it? I have been tracking with R-compounds, but not since last year, so I cannot imagine the oil beeing that old.

As you can see the throttle body was kind of dirty as well, cleaned this up.

[pilot4fn]

I had similar amount of oil in my plenum as I opened it on the spring this year while cleanign the throttle body which also looked like yours. Clened also the plenum and drove for a couple of weeks and then one morning the AOS died with a large puff of white cloud
This could mean that also your AOS is on a way out - somebody more knowledgable could chime in on that.

[Robert986]

Originally Posted by pilot4fn

I had similar amount of oil in my plenum as I opened it on the spring this year while cleanign the throttle body which also looked like yours. Clened also the plenum and drove for a couple of weeks and then one morning the AOS died with a large puff of white cloud
This could mean that also your AOS is on a way out - somebody more knowledgable could chime in on that.

Thanks for input, I guess it cannot hurt to change the AOS, just more work..

[Robert986]

Update:

Switched AOS, MAF, o2-sensors & spark plugs, still no luck.. Then I put back the oem cats, instead of the cheap eBay ones. o2 and HC back on zero again!

Anyone else had bad luck with eBay cats?

[pilot4fn]

Originally Posted by Robert986

Update:

Switched AOS, MAF, o2-sensors & spark plugs, still no luck.. Then I put back the oem cats, instead of the cheap eBay ones. o2 and HC back on zero again!

Anyone else had bad luck with eBay cats?

I had similar issues with 200 CPI cats. On this thread at the answer #2 is the reasons for the issues and how the MOT was cleared.

[Robert986]

Originally Posted by pilot4fn

I had similar issues with 200 CPI cats. On this thread at the answer #2 is the reasons for the issues and how the MOT was cleared.

Hmmmm... So heat.. extreme heat? What about if I put exhaust wrap all the way over the cats? I have wrapped the headers, maybe try to wrap the cats to. Anyone tried that?