HI, my 850 just failed its MOT on Emissions!!

[manback]

Hi everyone im new here.

sorry if this is in the wrong section.

my 850 has just failed its MOT on emissions and i was wondering if anyone had any suggestions as to what i could do to make it pass.

this morning i have had the exhaust heat shield off and noticed a crack in the manifold. i have managed to seal this, which has stopped the rumbling i hear in the exhaust note when i lift off the power.


does anyone think this may have solved the problem or does it take more than this?????

[laurence]

i would think this will solve the problem with it drawing air in through the crack it is probably giving the wrong signal to the lambda sensor telling it to increase and enrich the fuel,therefore using more fuel
laurence

[rippedoffagain]

I agree with what Laurence says, but also:

* When was your oil last changed? This has a significant effect on emissions. Some think the oil is just lubricant, but it also captures and traps blow-by gases. As the crank breather feeds back into the intake, dirty oil can release lots of filth which your engine has to burn off, resulting in increased emissions.
* Are your spark plugs, HT leads, dizzy etc all good?

[manback]

Originally Posted by rippedoffagain

I agree with what Laurence says, but also:

* When was your oil last changed? This has a significant effect on emissions. Some think the oil is just lubricant, but it also captures and traps blow-by gases. As the crank breather feeds back into the intake, dirty oil can release lots of filth which your engine has to burn off, resulting in increased emissions.
* Are your spark plugs, HT leads, dizzy etc all good?

in short NO.

i changed the oil about a 2 months ago. the dizzy leads are crap.
the oil breathers have always been a problem on this car, the little pipe at the back of the throttle body always have lumps of oil in it and creamy stuff and the one into the air filter leaks oil onto the filter itself.

all of that sounds expensive

[tarmacsurfer]

Time for a PCV system change! (not that nmuch money) You describe the flame trap housing as full of creamy oil... check to see if there is smoke puffing out of the dipstick tube (lift the dipstick out a bit whilst the engine is running). Sounds like you have the classic problem of blocked oil catcher and a PCV change will sort that out.