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Model specific boards => Golf mk3 => Topic started by: Len on 10 June 2009, 13:46
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had MOT test today (early) and failed badly on emissions!
CO2 readings very high, nearly double what they should be!
So the K&N will be going back on!
Spoke to Nick at RTech so can swap the old chip back in.
But my questions are what if this doesnt make it read right? What else should I be looking at?
Oxygen(lambda) sensor was changed a couple of years ago as was the CAT.
What other sensors could affect it?
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Lambda would be the likely culprit. Did you fit gen or GSF cheapie? I've heard that the cheaper ones really don't last long.
Nick
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If there is a leak in the exhaust it can make the co2 emmisions rocket sometimes! Try checking if there are any tiny leaks the MOT gut didnt pick up on. If not either the Lambda or Cat I wouldve thought!
Pete
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doubt the chip would make that much difference, many chipped cars still pass the emmisions test.
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Lambda would be the likely culprit. Did you fit gen or GSF cheapie? I've heard that the cheaper ones really don't last long.
Nick
Was a GSF one! :sad:
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If there is a leak in the exhaust it can make the co2 emmisions rocket sometimes! Try checking if there are any tiny leaks the MOT gut didnt pick up on. If not either the Lambda or Cat I wouldve thought!
Pete
Cant see or hear any leaks!
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poorly maintained car :huh: :undecided: :lipsrsealed:
and sits
and waits
:grin:
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:tongue:
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Gonna change the chip over as I know the other one was more economical so this new one is possibly over fueling!
Oh and Chuff didnt you notice my pics of the very shiny throttle body?
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when were your plugs changed last ?
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Len
Was the car warmed up properly before the MOT test? A cold car can give incorrect readings.
Have a look at the following link - may be useful
http://www.petercoopercarrepairs.co.uk/new_page_3.htm (http://www.petercoopercarrepairs.co.uk/new_page_3.htm)
Paul
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Oh yes the car was well warm and the tester gave it lots of revving and running!
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Yea thanks for that Paul, interesting reading!
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when were your plugs changed last ?
Ummmmmm........
Worth a check I suppose!
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Oh yes the car was well warm and the tester gave it lots of revving and running!
ok, well check the wallet for £20 and offer them to the tester next time, should pass with flying colours :laugh:
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Pretty sure you will have checked this, but check your map sensor hose for leaks( the one from
the T.b. to the ecu ). This caused my emmissions to skyrocket on my old 16v
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Yea will do, that pipe needs replacing anyway coz it was bodged before!
The tester guy did suggest checking all breather hoses!
Plugs are fine! No nasty deposits! Likewise the dizzy cap and rotor arm.
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Try some cataclean, i've used it to get old single point injection polo's through the test.
You can buy it from GSF.
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Here are the actual figures:-
Fast Idle 2500 - 2850 rpm
CO = .58% should be 0.3%
Natural Idle 725 - 925 rpm
0.68% should be 0.5%
He did a Second Fast Idle test and the was worse at 0.63% But the HC came down from 71ppm to 45ppm.
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Have you failed on hc as well?
Are you burning oil?
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No HC is well below would it could be! Max is 200ppm.
And no not burning much oil as shown by how good a state the plugs are in!
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No HC is well below would it could be! Max is 200ppm.
And no not burning much oil as shown by how good a state the plugs are in!
well i hope not! :grin:
Black plugs = running rich
glazed over, very white cores = running lean.
It should have grey/brown deposits.
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No HC is well below would it could be! Max is 200ppm.
And no not burning much oil as shown by how good a state the plugs are in!
well i hope not! :grin:
Black plugs = running rich
glazed over, very white cores = running lean.
It should have grey/brown deposits.
Exactly what they all are! Yes I checked all 4!
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Have you tried VAG com?
I would put my money on the lambda probe. Put a new one in.
Run the car down to about a quarter of tank of gas, put the cataclean in it, then take it for a long run up the motorway. Then refill with some super unleaded.
That will solve your problem :smiley:
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Pretty sure you will have checked this, but check your map sensor hose for leaks( the one from
the T.b. to the ecu ). This caused my emmissions to skyrocket on my old 16v
Yea will do, that pipe needs replacing anyway coz it was bodged before!
Try the pipe then, dont bother taking the car apart just to find the problem was the pipe.
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Have you tried VAG com?
No not yet - checking on here first to get views and info. :wink:
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Again why I'm asking on here first to save myself work!
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pipe pipe pipe! Get working Len!
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pipe pipe pipe! Get working Len!
Yea , yea!
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To be fair it wouldnt matter what chip your running the cat should sort the emmisions. If it was over fuelling that badly the plugs would be black as coal. I would get some cat treatment and take it for a damn good leathering round some B roads then a few miles on the motorway in a low gear keeping the revs high (4.5-5k). Its suprising the results.
Ive been an MOT tester for 10yrs and additive has come along in leaps and bounds.
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Yea been thinking the same! As the plugs are clean its not overfueling so must be either the CAT or lambda.
Yea I'm gonna read that info Paul gave again then go get some CAT cleaner!
Then a few blasts on M4 and A419! :evil: :laugh:
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Yea been thinking the same! As the plugs are clean its not overfueling so must be either the CAT or lambda.
Yea I'm gonna read that info Paul gave again then go get some CAT cleaner!
Then a few blasts on M4 and A419! :evil: :laugh:
or the pipe, remember?
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sort the vac pipes if in any dought and give it a good italian tune up. the abf in my mk2 got that treatment and ti managed better on the emission test without a cat
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Well Khare bear replacing that pipe has revealed other problems! :angry:
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Well Khare bear replacing that pipe has revealed other problems! :angry:
:grin: :grin: :grin: :grin: :grin: :grin: :laugh: :laugh: :laugh: :laugh: :lipsrsealed: :lipsrsealed: :lipsrsealed:
like what?
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See other tread on Hunting/Idle!
My guess is either something has just broke or by replacing the vac pies it has shown up something else that wasnt working! A sensor maybe
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blame Khare..........
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Oh I have been cursing him dont worry!
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lol Have u knocked something when u was messing around in your engine bay. (or get it professionally repaired and send khare the bill)
:grin:
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Well the other problem is solved, but still got same emissions readings!
Did the cataclean stuff and gave it a good rant and took it to a mate of a mates place and stuck it on the tester and got exactly the same readings!
So consensus now is its the CAT!
Advised to change crankcase breather and check Dizzy cap and rotor again as there is a slight hesitation and will check test again before I buy a CAT!
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I would change the lambda probe too.
If the cat is only a couple of years old, like you said, then something has f**ked it.
The probe is probably the likely cause.
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Possibly, but surely if the engine is running correctly as proved by the combustion colours on the plugs then the oxygen sensor must be doing its job?
Isnt it only there to change the air/fuel mixture as its before the CAT.
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Ummmmm been tinkering today with that crankcase breather and checking the dizzy cap fully and well I noticed a warning note on the cross beam by the bonnet catch! This says - Waring! overfilling with oil will damage the CAT!
:embarassed:
ooooops!
I have done that a few times!
Not by a great deal but could give an inkling why that crankcase breather burst! Hmmmmmm
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Sounds like your problem them matey. A lot of people don't realise that an over oil filled engine can be just as detrimental to it's health as a dry running one due to the extra oil pressure build up.
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Well have managed to get the CAT off after busting a bolt and by using loads of WD40!
Looks very black in there! :sad:
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Black as in cooked oil?
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Yes!
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Oops!
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well it will be black! its were most of the soot from the engine goes!!!!
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Sticky black!
Anyway all is good now!
Had codes read and no faults AND its passed its MOT.
So was the CAT!
Emissions test also showed that lambda maybe a little suspect too! Marginally over!
So Nick/Ben (RTech) was nowt to do with the remap! Realised that after checking the plugs and thinking sensibly instead of in a panic! :rolleyes: :laugh: