Decat

I've got a rattling cat on my 2003 1.9 PD and am considering replacing downpipe with a straight through non-cat one.

I keep seeing mention of decat and MOT with respect fo diesels, and people say it will pass with a friendly tester, but the cat should be there as it was originally part of the system. People go to the hassle of fitting fake cats just so it looks ok.

Anyway, i've just gone through the MOT manual (http://www.motester.co.uk/mot-general-information/mot-information-for-motorists/mot-test-checks-list-continued#exhaust), and the latest one says the following:

MOT Test of Exhaust and Emissions

The exhaust system will fail the MOT if:

• Part of the system missing or excessively deteriorated
  (from February 2014 a missing diesel particulate filter, if originally fitted, will be a Reason for Rejection)
• A catalytic converter is missing where one was fitted as standard (on vehicles subject to a full cat test only)
• Mounting is missing or damaged so that the exhaust system is insecure
• There is a major leak
• The system emits appreciably more noise than a similar vehicle fitted with a standard system in good condition.
• Class (v): Exhaust tailpipe positioned so that fumes are likely to enter the driver or passenger area.

Click to expand...

Note this line:

• A catalytic converter is missing where one was fitted as standard (on vehicles subject to a full cat test only)

Surely, this means that NO MOT tester can fail my car for no cat even if one was fitted as standard, and it applied ONLY to vehicles subject to a full cat test, and the diesel is subject to smoke test only.

Has anyone actually been failed with a diesel for no cat and then had to argue this with the tester?