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mot emissions failure only

Posted: Tue Jan 20, 2015 9:37 pm
by steveandmary
hi failed emissions test only for mot . will changing.. ?.. fuel filter help . changed oil plus filter and air filter. i have only bin using van for short journeys and no motorway driving. any ideas please

test limit applied 1.50 1/m
adsorption 1.94 ...........1/min 1.60 1/m.........1min
0.77 ...........1/min 1.62 1/m........1/min
3.84.............1/min 1.48 1/m........1/min

mean adsorption 1.57 zero drift 0.05 1/m

mean adsorption after correction 1.52 1/m

Re: mot emissions failure only

Posted: Tue Jan 20, 2015 9:40 pm
by Gasy
Yep try changing air filter
Put some of the expensive fuel in from petrol station
Give it a good thrashing up the motorway (use the hold button to keep it out of top gear )
Should help abit

Re: mot emissions failure only

Posted: Tue Jan 20, 2015 11:34 pm
by the1andonly
Diesel?
If so really warm engine up (10-20 mile) and thrash it to remove deposits (as gasy).
running around town is the worst, a good zup up motorway is good for you.
search topics italian tune up.
the change of oil is important.

also before retest warm up before taking for test.

Re: mot emissions failure only

Posted: Wed Jan 21, 2015 12:48 am
by Simon Jones
As above: it would benefit for a decent blast down the motorway in 3rd gear and then take it straight back for the test. Premium fuel and maybe some Millers diesel additive might help.

Re: mot emissions failure only

Posted: Sat Jan 31, 2015 10:47 pm
by David Edwards
if diesel bung some rapeseed oil in too, helps with emissions

Re: mot emissions failure only

Posted: Sat Jan 31, 2015 11:24 pm
by scanner
David Edwards wrote:if diesel bung some rapeseed oil in too, helps with emissions
At my last MOT tester couldn't detect any emissions and had to make the manual connection to the engine that tells the machine he was revving it up. The final print out showed 2 zeroes after the decimal point and that is at 170,000miles.
He tells me it is one of the cleanest diesels he tests.

50/50 veg oil and good (not supermarket) diesel works wonders. Driving the 5 miles to the garage with the hold button in helps as well.

Re: mot emissions failure only

Posted: Sun Feb 01, 2015 1:04 pm
by rita
The MOTT can only be (should) carried out when the engine oil temperature measured by a probe in the oil level dipstick tube is at least 80deg C or normal operating temperature.

Or the Computer says NO.

:D