Catalytic converter removal

bimble

Im reading stories online that catalytic converters are not a legal requirement on diesel cars in the UK. Does anyone know how true this is , and if so ,is it the same story here

Nissan doctor

bimble wrote: »

Im reading stories online that catalytic converters are not a legal requirement on diesel cars in the UK. Does anyone know how true this is , and if so ,is it the same story here

Link to these stories?

Plug

Vroooooooooooom boooooooooo.

bimble

heres the link http://www.ukpassats.co.uk/phpbb/viewtopic.php?f=8&t=40209

YouTookMyName

Decat pipe FTW. Can sell the cat and break even.

sean1141

they will pass the emmisions/smoke test without one but a tester could fail you for not having one i believe

mgbgt1978

As sean1141 said, diesel cars are only subject to a "smoke test". However they should be fitted with a cat.
Although there is no specific "cat-test" such as lambda etc, the tester can fail the car for not having the cat fitted.
By the way this is obviously only a visual check, so the cat itself could be empty..............

bimble

By the way this is obviously only a visual check, so the cat itself could be empty..............

I like your thinking, thanks for the replys folks

CiniO

Is there actually any point in NCT manual about cathalitic converter as a requirement
?

I would think if car is within emission limits without cat, then it should pass.

101sean

Nothing in NCT/DOE, it's smoke only. There's hundreds of Td5 Land Rovers out there with a de-cat front pipe (and no middle silencer either ). If a de-cat pipe isn't available, get rid of the contents. They are fitted so manufacturers can claim their engine meets EU emissions regs :rolleyes:

A diesel cat is a different animal to a petrol one which will fail if removed.

If the fun police get there way, any mods are likely to be banned at some time in the future.

_Conrad_

101sean wrote: »

Nothing in NCT/DOE, it's smoke only. There's hundreds of Td5 Land Rovers out there with a de-cat front pipe (and no middle silencer either ). If a de-cat pipe isn't available, get rid of the contents. They are fitted so manufacturers can claim their engine meets EU emissions regs :rolleyes:

A diesel cat is a different animal to a petrol one which will fail if removed.

If the fun police get there way, any mods are likely to be banned at some time in the future.

In the case of the DOE I have even had an old 2.8 trooper pass with a "home made" 3 inch system with no silencers, cats or anything at all. Now they gave out about it a bit as it was pretty loud but it still passed.

Had a terrano and pajero pass with everything but the backbox removed.
Know of a hilus with a very stack exhaust up the back of the cab which is literally just some 3 inch piping also.
The landcruiser has no cat and no middle box either and that's never had anything said at NCT time about it (It's taxed private, 7 seater hence nct) and it's got a fair amount of grunt and turbo whistle noise to it when standing behind it.

A diesel car should pass without the cat but may fail on excess noise if you start removing other things, i think they just expect 4x4s to be lod and nasty sounding anyway, even in the NCT as opposed to DOE.

vectra

Is there a worthwhile advantage to removal?

_Conrad_

vectra wrote: »

Is there a worthwhile advantage to removal?

Less restriction on the exhaust gasses getting out. On a diesel, in particular 4x4s and vans they're pointless waste of time and money as they don't get tested in the DOE, as 101sean says, only for smoke levels and the cat won't affect that.

With less restriction the turbo spools up faster which is a plus.

dougie-lampkin

101sean wrote: »

A diesel cat is a different animal to a petrol one which will fail if removed.

Not necessarily. I gutted the cat on my petrol car, and now it's a single (straight through) silencer and gutted cat system. The first image is my NCT test results with a cat and twin box system, the second is the results with a gutted cat and single box. It's certainly increased the emissions, but it's nowhere near failing.

On another note, the car originally put out just shy of 190 g/km of CO2. At the rate the exhaust is blackening these days I'd nearly feel bad if I knew how much it was pumping out now :pac:

bimble

Make me wonder how many people have bought new ones, after being misinformed by rogue garages and so on, I recently thought mine was kaput, and the cost of them is insanely high ,but weather it is or not, its coming off

CiniO

vectra wrote: »

Is there a worthwhile advantage to removal?

Few years back I removed one on 1.6 Bravo.
Instead they welded a pipe.

Except from different sound from exhaust, there wasn't really any other difference.

thats not gone well

dougie-lampkin wrote: »

Not necessarily. I gutted the cat on my petrol car, and now it's a single (straight through) silencer and gutted cat system. The first image is my NCT test results with a cat and twin box system, the second is the results with a gutted cat and single box. It's certainly increased the emissions, but it's nowhere near failing.

ah come on now Dougie, your yoke is still running a carb so its a bit too special to compare to anything designed after the 1950's :cool:

sean1141

CiniO wrote: »

Few years back I removed one on 1.6 Bravo.
Instead they welded a pipe.

Except from different sound from exhaust, there wasn't really any other difference.

you wont see any differance in a small n/a car. a large engined one or a turbo is a differante story do:D

vectra

sean1141 wrote: »

you wont see any differance in a small n/a car. a large engined one or a turbo is a differante story do:D

How much of a difference would it make to my one?
Cat removal and dpf delete ?

bimble

i,v a Passat 130 tdi should make a noticeable difference then, every bit helps, anyone driving a de-cated diesel Passat

barneygumble99

dougie-lampkin wrote: »

Not necessarily. I gutted the cat on my petrol car, and now it's a single (straight through) silencer and gutted cat system. The first image is my NCT test results with a cat and twin box system, the second is the results with a gutted cat and single box. It's certainly increased the emissions, but it's nowhere near failing.

On another note, the car originally put out just shy of 190 g/km of CO2. At the rate the exhaust is blackening these days I'd nearly feel bad if I knew how much it was pumping out now :pac:

your car passed cos its a pre 94 car so therefore no high idle test was done as u can see in the results.

2 stroke

dougie-lampkin wrote: »

Not necessarily. I gutted the cat on my petrol car, and now it's a single (straight through) silencer and gutted cat system. The first image is my NCT test results with a cat and twin box system, the second is the results with a gutted cat and single box. It's certainly increased the emissions, but it's nowhere near failing.

On another note, the car originally put out just shy of 190 g/km of CO2. At the rate the exhaust is blackening these days I'd nearly feel bad if I knew how much it was pumping out now :pac:

Quite a temperature difference between those 2 tests.

mgbgt1978

barneygumble99 wrote: »

your car passed cos its a pre 94 car so therefore no high idle test was done as u can see in the results.

Pretty sure his car was first registered in August 1994. It was manufactured in '94 also.

dougie-lampkin

barneygumble99 wrote: »

your car passed cos its a pre 94 car so therefore no high idle test was done as u can see in the results.

As above, it's a '94. And what does a high idle test have to do with the car sailing through? I have a cert for a petrol car that was presented with no cat, that's all I said.

And if you want to be technical, CO and HC would drop on a high idle test, and as it is CO is more than 10 times below the limit. If there was a high idle test with values for the old system, it'd still pass no bother.

2 stroke wrote: »

Quite a temperature difference between those 2 tests.

The first test had about a half an hour of waiting to be tested. The second test, I had no sooner parked outside the centre than your man took it onto the lane. I'd also doubt the accuracy of their temperature probe, it's an infrared gun that he points roughly into the engine bay from quite a distance. He might have aimed at the bonnet underside the first time and the rad the second time for all I know.