Have had problems getting my bug sti with ppp through the emissions test on last 2 Mot's despite getting the one prodrive cat piping hot,so i have the potentially crazy idea of buying a 2nd hand Milltek centre pipe which also has a sports cat therefore running with 2 sports cats which should make things easier at Mot time.

Would fitting a 2nd sports cat mean a remap?

 

I'd assume so, as you've introduced a greater restriction into the exhaust path. Depends how it was mapped in the first place. Talk to whoever mapped it I guess.

 

assuming no other issues more likely that your Lambda sensor is on the upper limit and would benefit from replacement - have done an identical car with similiar issues recently

 

My Prodrive sports cat barely scraped though the MOT last year. I should think this year will be worse. If it fails this year I think I'll just get a full decat pipe and buy a cheap standard downpipe to stick on every MOT.

 

Have you thought about buying a new sports cat say japspeed 200 cell.

 

Yes,my first thought was to buy a new cobra downpipe with built in sports cat but these are £400+ so was just looking for an alternative solution (cheaper)

The Japspeed version is £250 which seems reasonable,although it is a 3 inch pipe.

I'm thinking this would be a like for like replacement for the prodrive cat without need for a remap?

 

A car with no cats can pass the MOT emission requirements (mine did) so I'd be looking into why it's failing rather than throwing parts and money at it.
it could be something as daft as a vac leak or dud sensor. Has anyone run thorough diagnostics on it yet?

 

Have you read this?.

 

Its the same car Alyn!

Just looking for a way to get the emissions down a bit so it will
pass easier.

O2 sensor was changed as it was still on the 13 year old original as well as a check for exhaust and vac leaks although none found.

The problem seems to be the fast idle test where it eventually manages to scrape through after a few tries even though the cat was well hot just before test.

Fast idle:

CO = 0.28

HC= 17

LAMDA = 0.993

Natural idle:

CO = 0.17

 

Post a wanted add up bud, you can get 3" to 2.5 adaptor on gay bay.

 

from personal experience the "cheaper" sports cats are not the same quality at all and often no better MOT wise as having a pukka de-cat.........

 

Hence post wanted ad up.

 

Have just bought a standard OEM rear cat which i can swap for the prodrive cat delete pipe.

Should be easy to change (in theory!) and i suppose i could just use it at MOT time although not sure if it will make the car throw trouble codes with the increased restriction.

 

My mot tester likes beers and pizza, for some reason my car always sails through the emissions test lol

 

Sometimes its the simplest of things, years ago I had a car that failed (not a scooby BTW) but one of the readings was 10x what it should have been, can't remember which one, anyway it turned out to be a £5 coolant temp sensor.

Before you go throwing money at the car have a garage test all of the sensors and you may have a fault code sitting in the ECU that hasn't registered an EML...... worth a try?

 

Managed to get this done at the weekend,although did have problems with two of the exhaust nuts which needed intensive "persuasion" to free off.

Car is running fine so far with no fault codes.