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Discussion Starter #1
Hi guys

Last Thursday my Mini one failed its MOT for emissions. It failed on the following:

Fast Idle
CO =0.24 Fail
HC =244 ppm Fail

Second Fast Idle
CO = 0.74 Fail
HC = 331 ppm Fail

The garage suggested that it was the injectors, but another garage that looked at it today said it will not be injectors. So today a 'diagnostic specialist' looked at my mini, first thinking it was the lambda sensors as one was flat lining and the other was reading well out. After looking at these he found that one had already been replaced and that they were both infact fine as the new sensors read the same so he put the old sensors back in and didn't charge me for the new ones. He checked many other things of which i cant remember but he said there was nothing obvious that was wrong with the car, he said he'd be happy to keep looking for the problem but that'll obviously keep costing money.

More info:
About 2 years ago, the car had a new CAT which the mechanic today presumes was fitted around the same time as the lambda sensor as he believes there's an underlying problem that the car has had for a while and has only been scrapping through MOT's with new CAT's.
The car for the past few months has had a rough idle (drops when you put foot on the clutch for instance) but again the mechanic doesn't think its related to the emissions as the car runs fine apart from the weak idle and that the car failed the emissions on the fast idle part of the test. The mechanic today even tried getting it through another test but said no-matter how much you try and feather it, it wont pass.

Anyone got any suggestions as i only have a week out of the 2 week grace after failing an MOT, and no one is gonna want to buy a car with no MOT that is failing from emissions.

Thanks

Taylor
 

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Hi guys

Last Thursday my Mini one failed its MOT for emissions. It failed on the following:

Fast Idle
CO =0.24 Fail
HC =244 ppm Fail

Second Fast Idle
CO = 0.74 Fail
HC = 331 ppm Fail

The garage suggested that it was the injectors, but another garage that looked at it today said it will not be injectors. So today a 'diagnostic specialist' looked at my mini, first thinking it was the lambda sensors as one was flat lining and the other was reading well out. After looking at these he found that one had already been replaced and that they were both infact fine as the new sensors read the same so he put the old sensors back in and didn't charge me for the new ones. He checked many other things of which i cant remember but he said there was nothing obvious that was wrong with the car, he said he'd be happy to keep looking for the problem but that'll obviously keep costing money.

More info:
About 2 years ago, the car had a new CAT which the mechanic today presumes was fitted around the same time as the lambda sensor as he believes there's an underlying problem that the car has had for a while and has only been scrapping through MOT's with new CAT's.
The car for the past few months has had a rough idle (drops when you put foot on the clutch for instance) but again the mechanic doesn't think its related to the emissions as the car runs fine apart from the weak idle and that the car failed the emissions on the fast idle part of the test. The mechanic today even tried getting it through another test but said no-matter how much you try and feather it, it wont pass.

Anyone got any suggestions as i only have a week out of the 2 week grace after failing an MOT, and no one is gonna want to buy a car with no MOT that is failing from emissions.

Thanks

Taylor
timing chain,
pcv breather pipe cracked
 

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Another point to add is that it was smoke tested as well, which would rule the PVC pipe out right?
yep sure does timing chain then,
will explain a little deeper i have lost count how many times i have wrote something the same.
timing chain stretches and alters the over lap on the inlet and exhaust valves this also effects compression also causes blow back slightly in to the inlet manifold etc,
if car has more than 50k on it it well in the realms of being stretched but still sound ok as tensioner is still keep up with it, the tend to fail lower mileage on cars that have been run low on oil anything less than the full mark on dip stick is a no no with these engines, running 3-4mm above the full mark when cold is better way to keep them happy for longer, just need to get that veiw that a timing chain is life of engine its not unless its around the 60k mark that is,
so when chain stretches the car runs retarded unburnt gasses with fuel in ot get dumped on to the cat and destroys it as well as up stream 02 sensor, added extra fuel and heat because engine is running retarded, or special needs as some would say.
 

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Discussion Starter #5
The car has just hit 90000 and does go through oil like all minis do. There was a point where the oil was extremely low and the oil light came on, but i check bi-weekly now to keep on top of it.
 

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The car has just hit 90000 and does go through oil like all minis do. There was a point where the oil was extremely low and the oil light came on, but i check bi-weekly now to keep on top of it.
if its done 90.000 miles on the same timing chain from new then absolutely the problem, the 1.4 and the turbo engines suffer faster with timing chains form a lot of past experience with them, i done a peugeot last week same engine 70.000 miles full dealer history old couple who are driving around at 40-50mph and have had 10k oil changes all its life, found chain was stretched and bottom sprocket worn badly as well that was on a 2011 car,, i have seen turbo cars with 24.000 miles chain stretched was driven hard from new was run low on oil a lot,
at 90k yours will need doing, add to that you say run low on oil a few times would add to it maybe done some piston ring damages,, need to do a oil pressure test, need to do a compression test,, before doing anything else see what state the engine is in before even thinking of throwing a chain kit at it,
 

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I will talk to my mechanic tomorrow. Thankyou, will keep updated.
no probs you must do the basics first off, check oil pressure and compression so important, no point putting new parts on a engine that has been damaged from lack of oil
 
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