MOT Diesel Emissions Test

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Thu 12 Aug 2004 10:01
MOT Diesel Emissions Test - Mr Moo
When the diesel smoke test (revving the engine to full speed with no load)was first introduced, typical engines were Ford 1.6/1.8 idi and the Perkins Prima in the Maestro/Montego. Certainly, the Perkins units were known for being very smoky and could be tricky to get through the emissions test! Does anybody know whether the test is still the same or whether there are any plans to change it given the infinitely cleaner running of the latest common rail, Pumpe Duse and paticulate trap equipped HDi/D4D motors? Seems a rather archaic test for Euro III and IV compliant modern diesels!
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Thu 12 Aug 2004 23:24
MOT Diesel Emissions Test - Ivor E Tower
I queried this with the DVLA or whoever when the test was introduced as it is entirely unreopresentative of how a diesel engine is used. Basically it is because of an EU DIrective on how to test diesels, no doubt written by someone who does not understand how an engine works (and maybe someone who doesn't even have a driving licence). So I cannot see the test being changed in the foreseeable future. Although not an MOT tester or garage technician myself, ISTR from talking to my local MOT station staff when my diesel car's last MOT was done, that now the car need only be revved once until the governor cuts in, so long as it passes. Max of 3 attempts is now allowed, rather than mandatory rev it 3 times.
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Fri 13 Aug 2004 18:23
MOT Diesel Emissions Test - CG
I was around when my 406 HDi was being tested earlier this week. The engine was revved up to the governer 3 times, but not held there.
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