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How will they know the metal cylinder isn't a cat though?

For instance...

Sports cat or decat?

japspeed_mx5_de_cat.jpg
 
It maybe depends on the actual emissions like on a lot of petrol cars they do the cat test, maybe just on the really new cars
 
I always thought a car running no cat that should be was a straight fail anyway? Anyone had a de-cat genuinely pass an emissions test ?
 
The amount of exhaust gasses depend on a pass or fail, and you need a cat of some sort eg stadard or sports to reduce the gasses, so no cat means no pass
 
Ah ok didn't realise that about diesels. Always thought they got some form of test. Learn something new every day.
 
It says "where one was fitted as standard". I am guessing it will be a visual test ?

Yeh but the newer cars get tax cheaper etc for having lower emissions unlike me who gets bum raped by the government lol. That's why I think it's really to do with the newer cars, one of the reasons for CR and dpf is for emissions, it makes no sense that they use more fuel but give out less gas.
 
Yeah makes sense that they will do some sort of emission test on a diesel but i dont think it mentions that yet.

DPF, jesus what a nightmare that is. If you do a low milage you have to change the oil twice a year. How is that greener :rofl:
 
Only one way to find out, when mot time comes!
Cant be hooped removing and refitting mine, took the lazy option and got a garage to fit it as I didnt fancy dealing with sheared bolts on the turbo
 
Good job my mot station is "friendly" and incidentally my 57 plate pd130 ibiza is 10 quid a year cheaper to tax than my mates 53 plate pd130 leon. Never had any issues with any decatted petrol cars I've had either they've all been rather clean with decats, 200sx and 306 s16 passed with flying colours
 
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the OP refers to a de-cat on a TDi, which currently does'nt need a CAT to pass an emissions test .........mine hasn't needed one for the last 3 MOT's ;)

a de-cat on a petrol would be an auto fail because of the emissions it produces




" On vehicles that qualify for a full cat emissions test, check the presence of the catalytic converter."


do diesels require a FULL cat emisions test? :shrug:
 
Good point there, they dont actually have an emmisions test as such so maybe that doesnt apply?
The guidelines arent exactly specific and seem to leave a bit of a gray area around some subjects. Same with the HIDs and what it says about washers and self levelling, seen a few discussions about this also