Narrowly passed the MOT this morning - emissions

[Chilliman]

Hydrocarbons initially way too high at idle (650), had to 'increase' the idle a tad to bring everything in limits. No pre-cats but main cat is still in place. The exhausts do smell hydrocarbony at normal idle, and when cold/warming up there's lots of water/smelly black crap issuing from the tail pipes. I'd rather assumed this was condensation and 'soot'. Haven't checked the plugs, but the inside of the tailpipes are as black as it gets

Still, all good for another 12 months

[jr6yam]

The most common cause of high HC readings is a misfire
Of course there lots of possible causes of misfiring; sorry

I'd check the timing

[neal1980]

You need to find a more friendly MOT tester :-p

[rigga]

Was it hot enough when tested ?

[SILICONEKID340HP]

Chilliman said:

Hydrocarbons initially way too high at idle (650), had to 'increase' the idle a tad to bring everything in limits. No pre-cats but main cat is still in place. The exhausts do smell hydrocarbony at normal idle, and when cold/warming up there's lots of water/smelly black crap issuing from the tail pipes. I'd rather assumed this was condensation and 'soot'. Haven't checked the plugs, but the inside of the tailpipes are as black as it gets

Still, all good for another 12 months

Have you thought about an engine rebuild

[MPoxon]

Quite a few people have this issue when they swap to an after market ECU setup. I think they need a little bit of fine tuning.

Similar threads crop up from time to time eg:

http://www.pistonheads.com/gassing/topic.asp?h=0&a...

[haircutmike]

SILICONEKID340HP said:

Chilliman said:

Hydrocarbons initially way too high at idle (650), had to 'increase' the idle a tad to bring everything in limits. No pre-cats but main cat is still in place. The exhausts do smell hydrocarbony at normal idle, and when cold/warming up there's lots of water/smelly black crap issuing from the tail pipes. I'd rather assumed this was condensation and 'soot'. Haven't checked the plugs, but the inside of the tailpipes are as black as it gets

Still, all good for another 12 months

Have you thought about an engine rebuild

Maybe it's the wine Daz but your comments always make me laugh !

Richard, mine failed so I left it on idle for 15-20 mins just before testing, pleaded desperation and it passed! Gave him a score anyway and will visit him later this year!

[Chilliman]

Thanks for all the replys guys, to be fair, the MOT tester guys were good. We spent ages getting the best emission results, which before adjusting anything ocurred at 1900rpm. way too high for idle but ideal for an emission test.....

[SILICONEKID340HP]

Chilliman said:

Thanks for all the replys guys, to be fair, the MOT tester guys were good. We spent ages getting the best emission results, which before adjusting anything ocurred at 1900rpm. way too high for idle but ideal for an emission test.....

Would be a good idea to have a second map for the MOT ,with just a flick of a switch ,your engine will be running very rich at low rpm to mask the shunting problem..

I think Dexterios Megasquirt ECU`s have this option,so it`s just a case of burning your complete map on two number two and tweak the area`s needed for the MOT.

Phil will know the AFR`s needed for the imissions

Edited by SILICONEKID340HP on Thursday 2nd February 22:54

[taylormj4]

Mine failed on emissions two years ago. I asked the guy to test it via the other exhaust pipe and it passed ! Figure that one out.

Matt