eddiebeef

Had a Scoobysport downpipe fitted a few months ago and have just re-MOT'd the car (MY96 prodrive). It failed on emissions. HC passed ok but CO was around 0.6%, should be less than 0.3% for a pass.

Is it normal to fail MOT with just centre cat only??

eddiebeef

btw - previous MOT's have always had a CO reading of 0.0% before fitting the decat downpipe!!

eddiebeef

anyone?

smartecosse

what u need is a nice MOT tester who will do it as a non cat test.

Jolly Green Monster

iTrader: (4)

Was the car very hot at the time?

I believe the front cat is a cold temp cat and the middle a hot temp cat.. so middle one if working properly and the exhaust gases nice and hot is should pass an MOT..

That is how I remember it being explained anyway.

JGM

eddiebeef

not sure how hot they got the car. I did hear them revving it up quite a lot though!

I have now put the cat back on and the emissions came back down to 0.0% CO!

grahamfrary

Join your local Motor Club, find a realistic garage they recommend and take it there. They know if they fail it you are only going to change the pipe for the MOT then change it back, so what's the point?

Andy Murdoch

Eddie, that was my fear. I was just about to buy a front pipe decat for my STi 7 UK but the last thing I want is to have to change the thing out just to pass the MOT. I've been quoted around £100 to fit one so very quickly it becomes unviable.

A sportscat is around £500 but might be a better option in the long run.

I've seen few threads on this topic, especially on bugeye cars.

The dodgy MOT tester is not really an option as these guys wouldn't risk losing their testers licence for a dodgy test. The Dept of Transport go round doing just this sort of thing with obvious consequences.