1998 boxster decat & the emissions test

[wasz]

I understand only vehicles registered after 2002 need to have a catalytic converter fitted to pass the visual part of the MOT test.

My 1998 car has a rather ropey looking exhaust system. I'm thinking of ruining it by fitting a full stainless system.

I was wondering, will the 1998 2.5 pass the emissions part of the test without a cat?

It shouldn't throw a CEL light as the only lambdas are pre-cat on these cars.

I bought at auction a decat MX5 once (unknown to me), and it was touch and go on the emissions I had to try a few times on the tester with it red hot and running snake oil in the fuel.

Anyone got experience here?

Cheers.

Edited September 22, 2023 by wasz

[TV8]

You need to have a chat in advance with your local garage and explain it isn’t going to pass the emissions and ask if that is going to be a problem or not. 

[jonogt6]

On 9/22/2023 at 3:20 PM, wasz said:

I understand only vehicles registered after 2002 need to have a catalytic converter fitted to pass the visual part of the MOT test.

My 1998 car has a rather ropey looking exhaust system. I'm thinking of ruining it by fitting a full stainless system.

I was wondering, will the 1998 2.5 pass the emissions part of the test without a cat?

It shouldn't throw a CEL light as the only lambdas are pre-cat on these cars.

I bought at auction a decat MX5 once (unknown to me), and it was touch and go on the emissions I had to try a few times on the tester with it red hot and running snake oil in the fuel.

Anyone got experience here?

Cheers.

I would say not a chance. I don't know where you got the 2002 info from but I'm fairly certain it's all cars built from 1994. Unless you know some dodgy backstreet garage that'll forge the emissions docs it's impossible.

[wasz]

13 hours ago, jonogt6 said:

I would say not a chance. I don't know where you got the 2002 info from but I'm fairly certain it's all cars built from 1994. Unless you know some dodgy backstreet garage that'll forge the emissions docs it's impossible.

Here:

https://www.gov.uk/guidance/mot-inspection-manual-for-private-passenger-and-light-commercial-vehicles/8-nuisance#section-8-2

"You should reject all vehicles first used on or after 1 September 2002, where original emissions control equipment components are missing, obviously modified or obviously defective."

Also see:

[img]https://assets.publishing.service.gov.uk/media/5cf8f3a340f0b664039dcfed/Chart_3._Emissions_limits_of_non-passenger_cars_first_used_on_or_after_1_August_1992.png[/img]

I think the non-cat test applies? unless the EGA database says otherwise.

My MX-5 passed the cat test without a cat. Looks like my 1998 boxster might not need to pass the cat test.

Anyone here with a pre 2002 car without cats had test problems?