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woz
Wednesday 5th June 2013, 21:41
Just got a fail on emissions for the first time in 6 years of owning her :>(

HC's were OK at 34ppm (max=200) but the CO was .41% (max .30%)
Other salient point is she has been spewing a lot of smoke (and filled the MoT bay with blue/brown smoke on the first run up) but that was not mentioned on the sheet, and it was almost clear on the second run.

I need some experienced thoughts please-

I suspect that the oil smoke is not affecting the result as it would register as high HC 's??

On the CO front I recently fitted a set of refurbed and cleaned white injectors - could this be the reason for a high CO reading??

Before I start willy nilly attacking different bits - can anyone advise where the best place to start might be?

I havent done the PCV (yet)
I do have a new turbo and will need to do the vale seals but not planning to do now if it doesnt affect the CO reading. Thats the main target.
She had a 10k service two months ago (before injector change)
The lambda light does come on periodically so its clearly trying to self adjust.

Cheers

Woz

woz
Friday 7th June 2013, 08:32
Got it booked for a code read and diagnostic run on Monday at Hellikers. Decided to get some analyis before changing O2 sensors and CAT etcs.
Hoping its the O2 and I can clean the PCV and change the CAT when I do the exhaust. (Still the orig exhaust after 272k - the annual advisory on that is getting a bit boring now) LOL

M-R-P
Friday 7th June 2013, 08:38
Clean injectors would make it run cleaner, unless it's now overfuelling? (wrong injectors and or map?)
I doubt the PCV would cause it unless the catch tank is full and it's spewing oil and sludge into the intake.

Sort of stumped tbh, turbo oil seals? (I know it's new but..)

oblark
Friday 7th June 2013, 08:42
What where the orginal injectors ?

woz
Monday 10th June 2013, 12:03
Thanks Guys,
Orig injectors were the standard orange ones. Fuel consumption better now than before so was assuming no overfuelling going on. Could be wrong. Any comment on that is welcome:>)
Turbo has done about 170k as far as I know (105k under my ownership)

Had to cancel appointment at Hellikers today - things took a turn for the worse. On Friday I found oil all over the front and top of the engine and the under-bonnet sound proofing. :>((

Dipstick was not in properly. Pushed it in drove home, checked - it had popped out again. More oil everywhere.
Initially worried about a piston or ring having broken but hopefully only a blocked PCV or breather pipe so taking it all off for a clean. There was a lot of oil going into the intake anyway.

Initial fears of a piston or ring gone seem unfounded - I did a compression check and got 165,170,165,170,170 pretty much the same as last time (May2011) Unless I am suddenly getting a LOT more blowby on boost I dont think internals are bad enough to cause this "new" problem.

One possibility is the O ring on the dipstick I guess.

So I have a little list of things to do before I can even start diagnosing the CO reading. I am going to end up doing a load of stuff twice, as I aint changing the throttle body turbo and exhaust untl its got its MOT.

At least the weather is nice for outside jobs - it doesnt fit my garage!

Add to my frustration that the replacement ABS ECU I fitted threw a code within 5 ninutes so I have to crawl through the electrics too now.

Got an infected finger so good excuse to leave it for a day or so;>) - just got as far as the bottom bolts on the inlet manifold.

Turning a minor query into a saga.

WOZ

nobananas
Monday 10th June 2013, 13:44
What were the Lambda readings like on the emissions test ? To be honest .41 on CO is only just over the limit, (for BETS test anyway, what were the METS limits ?) often the cars are emission tested at the very end of the test when they have been idling for half an hour or so and 'choked up'. When we get one that close we tend to blat it down the road then retest the emissions immediately often goes through then.

oblark
Monday 10th June 2013, 14:45
With the engine running slowly pull the dip stick out abit and feel if they is air coming out the dip stick, if yes then slowly remove the oil filler cap. If the air coming out of the dip stick stops the it looks like your pcv is blocked and the sump is being pressurized.

My 850 is running blues and I'm getting 30 mpg but on over run I can get her to back fire :)

I would put the orange injectors back in for the mot.

Dangerous Dave
Monday 10th June 2013, 15:50
Mine was using lots of oil and blowing it out of places, changed the PCV which didn't sort the problem. I eventually sorted it by changing the valve stem seals (headgasket had gone so head was off anyway) and that cured the problem. If the stem seals have gone then the whole system will be getting pressurised, pushing oil through the pcv and into the intake.

On the injector issue, when you put larger injectors in the ecu adjusts the fuelling rate to what it needs (within reason) but it still thinks the smaller injectors are in, so the mpg will be incorrect (only way to cure this is to change the setting in the ecu)

nobananas
Monday 10th June 2013, 21:40
I would have thought that regardless of larger injectors being fitted that when the ecu goes into closed loop then the fueling would be adjusted so that the Lambda is seeing a stoichiometric ratio of 14 to 1 and overfueling would only occur when it drops into open loop when accelerating etc.