75ZT Community

raistlin · Posted 05 Feb 2014, 19:31 #1

Topic of discussion at work today threw up the possibility that if a cat was fitted to a diesel during manufacture it must be fitted to pass the MOT.

Does anybody have anything other than speculation regarding this please?

Mick · Posted 05 Feb 2014, 20:30 #2

https://www.gov.uk/government/uploads/s ... 1-2014.pdf

Pretty definitive.

http://www.motinfo.gov.uk/htdocs/m4s07000101.htm

raistlin · Posted 05 Feb 2014, 20:33 #3

Yes, it is.

I wonder though, how do the testers know whether one was fitted as standard and whether they can inspect the cat if the undertray is fitted?

Mick · Posted 05 Feb 2014, 20:40 #4

You'd have to ask those that make the rules.
I have had caveats written on my MOT's "some parts could not be inspected because under tray fitted" and same for engine cover. I wonder if that get out clause for the MOT inspectors has been addressed. I know they were or are not allowed to dismantle anything to gain access.

raistlin · Posted 05 Feb 2014, 20:55 #5

I had better get a scrap cat, dig the guts out, and get it fitted then. Thanks Mick.

Duncan · Posted 05 Feb 2014, 22:01 #6

I think the problem would come, if the removal of the cat pushed the emissions outside of the limits. With a petrol this is very likely, but I've heard its less likely with a diesel.

The same (about not removing but how do you tell) is also the case with DPFs although we don't have those on our cars.

DaveyC · Posted 05 Feb 2014, 22:19 #7

It may look like a cat but if its got no internals, how the heck will the MOT guy know on a diesel? Thinking of taking the internals out of my cat (my the actual cat, the RSPCA might have an issue with that - LOL).

Dave

raistlin · Posted 05 Feb 2014, 22:57 #8

Duncan wrote:I think the problem would come, if the removal of the cat pushed the emissions outside of the limits.

I thought it was still only the smoke opacity test for diesels Duncan?

persuer · Posted 05 Feb 2014, 23:08 #9

The only test carried out on diesel cars is smoke density (as related to particulate matter emissions). To carry out this test, the engine is accelerated several times and the vehicle must not emit â€œdense blue or clearly visible black smoke for a period of more than 5 secondsâ€ at idle or â€œdense blue or clearly visible black smoke during acceleration which would obscure the view of other road usersâ€.

source.http://www.car-emissions-explained.co.u ... sions.html

Bolin · Posted 06 Feb 2014, 00:05 #10

I suppose if the cat is gutted, make sure the opening is done on the top side so can't be seen from underneath

DaveyC · Posted 06 Feb 2014, 07:43 #11

Here's what I have seen done before. My friend has done this on an Audi A6 3.0 TDi. Made a big difference in pick up and it pulls better in the gears now.

http://www.youtube.com/embed/2rxUDFRBeSo

This is a MUST an a MK3 MR2. The pre-cats on these breakdown and ruin the engines (pre 53 plates). This is what is very common place on their club website.

PaulT · Posted 06 Feb 2014, 07:54 #12

Devil speaking

'wonder what sentence a magistrate would give for obtaining an MOT under false pretences.'

Jürgen · Posted 06 Feb 2014, 11:33 #13

Duncan wrote:[...] with DPFs although we don't have those on our cars.

Well, Duncan, not in each and every case.

Removing the DPF (Diesel Particulate Filter) from my 75 won't be legal over here.

Bolin · Posted 06 Feb 2014, 12:50 #14

I thought a DPF was different to an EGR (Exhaust Gas Recirculation Valve) valve? Or do German spec 75/ZT's have a proper DPF?

Mick · Posted 06 Feb 2014, 13:15 #15

DPF, In Germany one has to be retro-fitted. They were not fitted at manufacture to any Rover 75 or MGZT

Jürgen · Posted 06 Feb 2014, 13:54 #16

As Mick said, the DPF is a retrofit solution. Although it's not mandatory, you won't be allowed to drive into some urban areas without one anymore.

Bolin · Posted 06 Feb 2014, 16:42 #17

Ah thanks, I see, that makes sense. I didn't realise that anti-emissions rules in Germany were quite that strict as to require bits to be retrofitted. I remember that my sister had to get some sort of certificate so she could take a 2006 Skoda Octavia to some parts of the country.

raistlin · Posted 06 Feb 2014, 17:01 #18

DaveyC wrote:Here's what I have seen done before. My friend has done this on an Audi A6 3.0 TDi. Made a big difference in pick up and it pulls better in the gears now.

http://www.youtube.com/embed/2rxUDFRBeSo

This is a MUST an a MK3 MR2. The pre-cats on these breakdown and ruin the engines (pre 53 plates). This is what is very common place on their club website.

Thanks Dave. I appreciate your help mate but my original query was an academic rather than practical question

I certainly don't intend to attack VeeKay with a hammer and a large screwdriver / chisel :lol:

Steve (Arctic) actually directed me to an interesting discussion on much the same lines on the Club forum which I'm following with interest.

Regarding the enforced retrofit of a DPF in Germany... perhaps our rules aren't quite as draconian as they might be... erm... YET.

Duncan · Posted 06 Feb 2014, 22:22 #19

raistlin wrote:
Duncan wrote:I think the problem would come, if the removal of the cat pushed the emissions outside of the limits.

I thought it was still only the smoke opacity test for diesels Duncan?

Sorry, hadn't thought of it from that point of view. There are emissions measurements for new cars, so I forgot for diesels they don't yet test them. Or is that the case for newer stuff? TBH I don't know anymore.

Arctic · Posted 07 Feb 2014, 00:11 #20

A link for those whom may have removed them and might need to replace them, I note when you put in the details of your car these will not fit a CDTi 2004:confused:but will fit up to a CDT 2003 Arctic http://www.ebay.co.uk/itm/181200148468? ... 1438.l2649

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