Failed MOT! :-( HELP!

[Surf01]

No, you're correct. But ~2,500rpm (for 20 seconds) may seem like a lot to someone that's not used to hearing an unloaded engine at that kind of revs.

You are probably correct but I would estimate it was at least 3000 revs. Only by revving the engine to about 3000 I was able to duplicate it.
Besides using veggie oil and a mix of diesel, are there any bio branded fuels that help keep the engine clean? Generally I use BP or Shell. Has any one tried BP Ultimate which is about 7p dearer?

[Karma Supra]

I hate the way they over rev on MOTs...

They did it to me too, Like you my truck hardly gets many revs, and the first time you do a load of crap comes out. A good blast first usually does the trick!

You might find that a clean new exhaust with no crap in it minimalises the effect too! (this is just my theory and not actually based on anything)

[Surf01]

The complete exhaust system from Roughgtrax has set us back £223. Thought I might as well have the whole lot replaced while we have a bit of cash instead it failing as per Sod's law when you have no money which is most of the time!

Hopefully you are right and a clean exhaust will show clean emissions. Probably won't use supermarket fuel again just to save £2.50!

[steved]

The 2500 rpm is only to purge the system and do a visual check during the actual emissions test it is revved up as far as the governor will allow 3 to 6 times then if its below 3.0 parts per million it passes if not it fails, dirty engine oil will sometimes cause them to fail changing the oil and running a fuel system cleaner through the system will normally get them through.

[shokenore]

The complete exhaust system from Roughgtrax has set us back £223. Thought I might as well have the whole lot replaced while we have a bit of cash instead it failing as per Sod's law when you have no money which is most of the time!

Hopefully you are right and a clean exhaust will show clean emissions. Probably won't use supermarket fuel again just to save £2.50!

FYI
my surf is ALWAYS run on "supermarket" fuel as far as I am aware Sainsbury's do not actually run or own a oil refinery so they probably buy their fuel from one of the big four .
I have never had any problems with the fuel.Ever.
My Vito has with a very few occasions always been filled up with from the same station (sainsbury's)

The black smoke you are having an issue with is common .

Do as others have said and before you take it into the MOT station get the engine nice and hot drive it like you stole it ie bury the pedal in the carpet a couple of times .(obviously whilst being aware of all local traffic laws and regulations)
Run your favourite Fuel conditioner through and make sure the air filter is clean and you should be fine.

[BUSHWHACKER]

The 2500 rpm is only to purge the system and do a visual check during the actual emissions test it is revved up as far as the governor will allow 3 to 6 times then if its below 3.0 parts per million it passes if not it fails, dirty engine oil will sometimes cause them to fail changing the oil and running a fuel system cleaner through the system will normally get them through.

Bit anal ain't it?
What happens if the timing belt snaps during the high RPMs, will you pay for the damage?

[shokenore]

Bit anal ain't it?
What happens if the timing belt snaps during the high RPMs, will you pay for the damage?

Yes

No


They have a little disclaimer mentioning "if you have any concerns about the emission test please consult your tester"

[MWS]

Would it not be possible, then, to wind out the stop on the pump to prevent it from revving too highly? As Andy says, a good veggie blend will do wonders to bring down both your emissions, and particulates. Pre MOT I always, also put in a bottle of injector cleaner, and a litre of ATF. The MOT man always has a little chuckle at how low the emissions figures are on the "Chip shop special" (His name, for it, not mine).

[Apache]

You can buy a special ball bearing that reduces black smoke...

[Surf01]

Surf was serviced less than a month ago so no issues with oil. Goes in this afternoon for new exhaust and MOT retest.
I took it for a good blast up the M5 motorway from Strensham to Worcester after putting in a good dose of Redex. Had the overdrive switched off. Thought I was driving a V8!
Pull up once off the M5 and gave the engine a good rev up and over 3000, but still the wisp of black smoke initially as you floored it. Here is hoping.
Update you later.

[Kiwisurfing]

Poor buggers getting tested on smoke, its a diesel its what they do when reved suddenly

Gotta love my country we dont have emissions testing and I use it to the fullest extent, every time I get a !!!!!!! boy racer following too close I drop it into 5th and floor it resulting in them backing off real fast in a cloud of black smoke

[Surf01]

Poor buggers getting tested on smoke, its a diesel its what they do when reved suddenly

Gotta love my country we dont have emissions testing and I use it to the fullest extent, every time I get a !!!!!!! boy racer following too close I drop it into 5th and floor it resulting in them backing off real fast in a cloud of black smoke

I don't mind the emissions test too much, but dislike it when they rev the engine to check it. Seems this emissions thing is going down the tubes as according to the Telegraph the government is now looking to either taxing or increasing tax on "green" cars as they are losing income even though our roads are no better!

[tonupteabag]

I don't mind the emissions test too much, but dislike it when they rev the engine to check it. Seems this emissions thing is going down the tubes as according to the Telegraph the government is now looking to either taxing or increasing tax on "green" cars as they are losing income even though our roads are no better!

I've been wondering how long it would take! On paper it seemed to be viable, now it seems it wasn't! The prats should just stick it on fuel and be done with it, at least then if you drive a lot you pay more than the person who only uses the vehicle for the weekly shopping trip.

[Wolfracer]

I've been wondering how long it would take! On paper it seemed to be viable, now it seems it wasn't! The prats should just stick it on fuel and be done with it, at least then if you drive a lot you pay more than the person who only uses the vehicle for the weekly shopping trip.

Its not about the use or maintenance of roads though is it? More money raised by taxing everyone and then taxing some a lot more...

Road fund through tax on fuel would be far too fair...

[Sancho]

No print out for the test. Just visual and no test apparatus.

Do you mean the emissions test consisted of revving the nuts off it and seeing if any smoke came out??