diesel emission test - help!

[docchevron]

You're all missing the most obvious cause which is pump timing, do it properly and you'll get a clean exhaust.

Hadn't missed it, but it's rather unusual for the timing to get altered.
Unless it's a tooth out on the belt, but then it would run like stuffed pig.

What year is the car? if it's a K reg> then it'll have the fuel filter on the thermostat housing, if it's < K reg then it'll have a seperate filter (choice of 2) mounted on the OS wing just behind the LHM tank.

[Gibbo2286]

Man made faults doche, always the hardest to find and correct, I've had no end of vehicles with the pump timing out and the owner having no knowledge of how it happened.

I bought an LDV milk float off another trader because it filled the street with white smoke and was considered 'knackered', half an hour with a dial gauge and it was running clean and worth five times what I paid for it,

Likewise a turbo diesel ZX earlier this year, stunk of unburned diesel, smoked the street out, had recently had a new head gasket so assumed it was likely to be belt timing, belt timing was spot on, pump timing wasn't, resetting it cured the problem. Gibbo.

[scarecrow]

It's amazing what these engines will put up with - Steve, who bought my old rd estate discovered that the pump was loose! The car still drove okay, and I'd put the smoky starting to a glow plug issue He reset the timing and I understand the car runs a whole lot better now.

Which emissions were high (CO2, NOX, what?) As that would surely give someone in the know a clue to the possible cause.

[tim]

Filter problem solved, thanks guys. The one in there was brand new and anyway I'd been sent the wrong filter so I couldn't have changed it . I shovelled out the diesel therein and added an equivalent of cleaner, ran it for a mo and turned off. It will now sit overnight, let's see if that does anything. Not convinced..... yes, point taken about pump timing but checking it seems to be a bit of a game if you go by Haynes (yes, I know, but what else is there?), not a simple job, not quite like strobing the timing or checking a points gap. I'll read the words again and see if if the aargh factor diminishes at all. Gonna have to do something, whatever.
The emissions sheet doesn't mention CO2 or NOX, it simply covers the smoke test which over 6 peaks was 9,9.3,2.38,5.06,4.48,4.71. The average was 4.74 which is a fail, if I read the thing right the max is 2.50. Oil temperature was 81 degrees. This is wayyy above the figures on the previous test.
I got my dead blower fan working at last, exactly the same problem as featured on the article on this elsewhere on the site. Poor earths - I linked wires 2 and 3 together off the plug and hurrah, I can demist myself while driving too and fro from the MOT shop....[/i]

[scarecrow]

Ask the garage to check it for you...

[docchevron]

oh, thats not THAT high then!
I've had so high before now the tester has shut down!

Point taken Gibbo but I assume the car was known to be ok before, and the pump hasn't been arsed about with since?

I'd turn the fuelling down 1/8th turn, with the fuel system cleaner in it I reckon it'll piss through.

[DavidRutherford]

oh, thats not THAT high then!
I've had so high before now the tester has choked to death and fallen down!

EFA.

Oh, sorry, you didn't mean the testing inspector, just the test unit?

[docchevron]

The lesser spotted David! Hows things?

One of the many things that pissed me off with my last tester (who I'd used for years until he was laid off) was his reluctance to test anything that black smoked when booted.
It was fine until they got the new optical machine and he got all arsy saying any soot covered the optic lens and caused the machine to go out of action.
So he'd fail the car for emissions without actually testing it.
Despite the fact I'd already emissions tested it before presenting it and it passed on the fast pass.
Tosser he was sometimes.

[sarahjaneking]

I got my first bus through an emissions test using 30% svo 70% diesel. Bit risky if you suspect dodgy injectors or pump though. Apparently bio-diesel has lower emissions (see below taken from biodiesel.org) so it may be worth seeing if there is any for sale locally??????????


How do biodiesel emissions compare to petroleum diesel?
Biodiesel is the only alternative fuel to have fully completed the health effects testing requirements of the Clean Air Act. The use of biodiesel in a conventional diesel engine results in substantial reduction of unburned hydrocarbons, carbon monoxide, and particulate matter compared to emissions from diesel fuel. In addition, the exhaust emissions of sulfur oxides and sulfates (major components of acid rain) from biodiesel are essentially eliminated compared to diesel.

Of the major exhaust pollutants, both unburned hydrocarbons and nitrogen oxides are ozone or smog forming precursors. The use of biodiesel results in a substantial reduction of unburned hydrocarbons. Emissions of nitrogen oxides are either slightly reduced or slightly increased depending on the duty cycle of the engine and testing methods used. Based on engine testing, using the most stringent emissions testing protocols
required by EPA for certification of fuels or fuel additives in the US, the overall ozone forming potential of the speciated hydrocarbon emissions from biodiesel was ne[/code]arly 50 percent less than that measured for diesel fuel.[/code]

[MULLEY]

I had heard something similar regarding a reduction in emissions by using biodiesel. I tried 70% & my txd didn't like it, 50% & she was ok, always felt down on power & fuel economy wasn't as good, so have stopped using the stuff as it was only approx 10p/l cheaper than regular derv, so really wasn't saving that much tbh.

[Defender110]

Does this mean when we're out I won't be following that constant smell of Fish and Chips down the motorway any more?

[MULLEY]

Bio matey, not veg If anything, if i was using bio, it might smell a bit like doughnuts

[docchevron]

water injection reduces emissions too, by a huge margin, but that a bit complicated to do!

[tim]

Problem solved - MOT passed and the wagon goes like the proverbial off a shovel. Well, all those replies and all that expertise and yet none of you got it! I will tell you, but please remember that before you start sniggering, I could have kept quiet about this. And it could have happened to you.......
To recap, 19TXD non-turbo laid up in a wood for four years. Passed last emissions before layup with flying colours. Fresh diesel, clean filter, engine cleaner, fresh oil, the biz. And yet, when floored, clouds of smoke and a chronic stutter. Valid points made about the pump and timing but no-one had been fiddling with it and it was fine at low revs. I have reasonable mechanical experience and my gut feeling was that it was entirely due to the lay-up. Oi were right......
It was clear we were getting nowhere so I talked to a fuel injection specialist who said he reckoned a blockage - injectors not getting the correct mix leading to smoking and stutter. So I booked in (he also does MOTS) and had a perfectly pleasant run down to Hailsham. Ten minutes later he had tested everything he could and said there was nothing wrong with the dieselly side of things. Much scratching of heads. He then pulled out the air filter.
Now this was the first item I'd looked at when compiling a shopping list, we weren't going to spend any more than we needed if the car was just going to be given a terminal failure on the MOT. It was near as dammit new, and clean. Tick box, move on. WRONG.
The problem, people, was... mice. Yes, small furry bastards. They'd found the inlet tract, followed it into the airbox and found a beautiful new family home. They then went to mouse Ikea and imported several bucketfuls of broken hazelnut shells and selected forest floor products to make a snug little retreat. So the airbox had become a mousebox, and the exit, being a bit draughty, was securely plugged. Little shits. How we laughed....
Never mind - the wife laughed non-stop for ten minutes, the two tins of diesel cleaner did some good and it was all educational stuff. There is NOTHING in Haynes about mice, OR squirrels (which I really hate - does anyone know where I can buy the bumper sticker 'squirrels - nature's little speed bumps'? I have seen one but couldn't find the owner.)

[citronut]

so your car could not play the mouse organ then ,

you obviously dont have a cat fitted either

regards malcolm