1.9 TDI owners with a decat - Are you still passing MOTs?

Jun 30, 2021
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Hi guys
I'm well aware the MOT tests are more stringent these days, you cannot have an obvious decat straight pipe in place and expect to pass an mot.
What about the pipes designed to look 'stock(ish)' like these
Screenshot 2022 05 15 183019

Does anyone have one fitted to their 1.9 TDI, and are you getting any issues with an MOT test since having it installed? I'm inclined to think this would pass a visual check and as long as the smoke test was OK you should be good to go, but I'd be interested to hear some real world results.
Nope , custom 2.5" stainless .

Other reasons for such a low score is , egr delete , 507.00 , JASO FB 2 Stroke oil , 2-EHN and a new thermostat .
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Regarding your other mods I have/use all but the 2 stroke oil, that's a new one on me.

What brand oil do you use, and how much? I'm assuming the 2 stroke has some lubricating or cleaner burn properties?
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That alone halved my mot smoke opacity test from 2.0 to 1.0 , but the underlying issue was a bad thermostat .

The 2 Stroke is a mineral based low ash and acts like a Cetane number booster to lessen diesels combustion lag so more complete combustion of diesel fuel molecules occurs so therefore less incomplete fuel molecules ( soot ) .

20201111 090014

I put in both my diesels around 200ml 2T and 40ml 2-EHN in pre made up used Redex bottles and now and then Redex itself , waaaaaaaaaaay cheaper than the con that is premium diesel .
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Gaz you almost make me want to buy a diesel again just so I can play the chemist!