Clean Diesel

[electrocoolman]

My 2003 D5 163hp 210,000miles has just sailed through its MOT yesterday.

Smoke test was 0.05 (I believe the limit is 4.0?). Anyway comments from tester was that it was very good, and lovely sounding engine.

Premium diesel (Shell V-Power or Costco), Regular services, Mobil 1 turbo diesel oil.

Why can't the road tax be set by referring to the emissions test at the annual MOT?. People would then service their vehicles better. Also get rid of cheaper low quality diesel fuel would help clean up the emissions.

[tt82]

My dad advocates this, however there are currently to many 'friendly' MOT testers who have ways of rigging emissions tests so it wouldn't work!

[davebb]

Hi The mot does not do a emissions test, it is just a smoke test for diesels
Dave

[jamie1131]

Don't be fooled into thinking you have a clean car just because you have a low smoke test result. At one MOT I had an advisory to say "smoke result too low for machine to read". That doesn't in anyway mean the car is clean, just that the DPF is doing its job. All the other emissions will still be belching out!

[dme123]

The smoke test for diesels is virtually worthless with any modern diesel engine with ECU controlled fuel delivery. It was for the older mechanically governed injector pump engines, which injected the same amount of fuel at a given RPM irrespective of load.

A modern car will know to inject almost no fuel when the engine is being revved at idle. Rest assured your old diesel with no particulate filter and no NOx reduction equipment chucks out all sorts of extremely unpleasant stuff when you are driving along, several orders of magnitude more than a modern diesel running on Tesco cheapy diesel ;-)

[skyship007]

Originally Posted by electrocoolman

My 2003 D5 163hp 210,000miles has just sailed through its MOT yesterday.

Smoke test was 0.05 (I believe the limit is 4.0?). Anyway comments from tester was that it was very good, and lovely sounding engine.

Premium diesel (Shell V-Power or Costco), Regular services, Mobil 1 turbo diesel oil.

Why can't the road tax be set by referring to the emissions test at the annual MOT?. People would then service their vehicles better. Also get rid of cheaper low quality diesel fuel would help clean up the emissions.

Using top of the range diesel is not really necessary if you use a direct feed injection system cleaner like Liqui Moly diesel purge to fill up the fuel filter housing when the element is changed.

For any non DPF diesel (2004 and before) the oil should be an Acea A3/B4 0 or 5w40 full synthetic post warranty. Some oils that say turbo diesel are C3 rated.

None of the major oil companies sell low quality diesel, unless it's from a marine station. That fuel has high levels of Sulphur which is not good news at idle as it forms acid.
In some warmer countries overseas diesel can also contain some alcohol additive that is used as a cheap biocide and the reverse is then true, it's OK at idle but not good at full power.

It would not work to base any tax on an emissions test, as the results vary from day to day and it would also result in a lot of bribes etc.

[steadvex]

Your engine isn't tested here, but for reference check out the figures for the newer 2.4's with lots of snazzy filters and wonder how clean yours is !

http://equaindex.com/

Quite interesting to note a lot of petrol are just as bad of not worse than their diesel counterparts!

[skyship007]

Originally Posted by steadvex

Your engine isn't tested here, but for reference check out the figures for the newer 2.4's with lots of snazzy filters and wonder how clean yours is !

http://equaindex.com/

Quite interesting to note a lot of petrol are just as bad of not worse than their diesel counterparts!

Very interesting figures on cold starts in particular, as I did not realise how long it takes for the EGR & CAT to function, or how short most folks trips are. Some of the 5 minute folks really should buy a push bike or get an electric pre heat system fitted.

Oddly enough the petrolheads forget that apart from the fact that real world emissions are just as bad as diesels, around 300 people burn to death in post crash fires in the UK each year, as they don't fit automatic engine fire extinguishers to most cars.