MOT Fail

[Kusunagi]

Hi All, has anyone had an issue with failing the MOT on smoke test? My 2011 2.0 Cdti just failed with a reading of 0.80.
Last year this was a pass.
They are using the vehicle manufacturer plate readings now, which for mine is 0.50. I found out after if I removed the plate they would have tested it at the standard 1.50, not sure if that is true?
Its too late now for me and I'm now trying to find a way to get the emissions down for the retest.
Anyone had any suscess with lowering the emissions? I'm trying Cataclean and the Italian tuning method.

Cheers All

[PeteH]

"... The Italian tuning method"?

[Kusunagi]

Yeah. Basically thrashing the hell out of the car. To be honest I don't like doing it. It's against my normal driving style. The mechanic told me to put some additive in and red line every gear for about a 20 min drive. Blows all the soot etc out.

[PeteH]

Oh, I thought it would involved shoving a Cornetto up the exhaust pipe while singing 'O Solo Mio'

[ilunn]

I use this stuff but not as the instructions, What i do is fit new fuel filter but half fill it with the forte start engine only for very short time (enough time to get the forte into injectors) I then switch engine off and leave it over night to soften build up of crap in fuel system/injectors, pour rest of bottle into tank (best if quite low as stronger concentration) then give it good blast as mentioned already. would also benefit from second bottle in tank before you fill up again.

https://www.amazon.co.uk/Forte-Advanced-Formula-Diesel-Treatment/dp/B008COEA9S/ref=asc_df_B008COEA9S/?tag=googshopuk-21&linkCode=df0&hvadid=255605292182&hvpos=1o2&hvnetw=g&hvrand=11532595259108512535&hvpone=&hvptwo=&hvqmt=&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=1007258&hvtargid=pla-718731186855&psc=1

[Kusunagi]

Lol. I wish that kind of Italian tuning worked peteH. Be much cheaper.
Thanks for the info ilunn. My friend uses forte and swears by it. Maybe I could try it with the cataclean stuff I have as have another bottle, I'm guessing they work the same?
I need the emissions sorted for next week. I'm considering trying Thermaclean or that hydrogen cleaning. Not sure if they are just cowboys though?
Anyone on here tried them? I know it works for Dpf but not sure on emissions.

[lizzard-t]

Hello Kusunagi, from personal experience of carbon cleaning in general , you are better off setting fire to the money you would spend on carbon cleaning ,it gives you the placebo effect .
You could try an additive, but that will not lower your smoke opacity limit .
If you are good with spanners , then I would
Remove the intake hose to the throttle body
Get some MR Mussel oven cleaner ( use gloves and loads of rags , open the throttle butterfly
And spray that in , then get a bottle brush and work,it around when you have done that leave for 20 mins .
In the mean time check induction hose and do the same
Remove MAF sensor and get some electrical contact cleaner and spray on the sensor ( behind the gauze)
And allows to dry .
Remove MAP sensor use contact cleaner again ( thease normally get quite filthy with carbon ) and use a cotton bud to remove build up,.do not prod it as it's an electrical component!
Remove EGR valve and use carborettor spray and clean it ( thease get quite filthy )
Put back MAP and MAF sensors , and EGR valve
Go back to inlet manifold and wash out using carburettor cleaner and rags and do the same with the induction hose
Once above all done
Put everything back together
And then take for a sprited drive you will find that when you put you foot down that you may get a bit of black smoke out the back at first don't be alarmed it's because you have loosened carbon deposits.
Parts required
Oven cleaner
Carborettor cleaner
Electrical contact spray
Cotton buds
Rags
Gloves
I do this every 6 months to keep things as clean as I can .

[Butt0ns]

Call me stupid but failure of the 'smoke test' means the DPF is either not present or working as designed. Not present would be the assumption as not working as designed would lead to blockage and other issues. Fit a DPF and you'll pass the MOT.

[lizzard-t]

Hello Buttons , no your not being stupid, that's a very fair comment .
And as with any diesel fitted with a DPF , or any diesel to that matter , it depends on how it's been driven , but diesel cars do produce a lot of carbon ( soot ) which just sits in the intake system clogs up the intake system , so the car is not abe to breath properly.thus creating higher opacity levels , no matter how good or bad the DPF is .
His level is 0.80 and the data badge is 0.50 which is about right for a car fitted with a DPF of that age .
He's not far off a pass with that level . If he had a opacity level of 1.00 or above then he would be looking at the emissions side as at fault .
A clean as I discribed Should bring the level down for a pass , but like anything, if it's not looked after then it will come back next year to bite him again .

[Kusunagi]

Hi, thanks for the information guys. The car does have a dpf it hasn't been removed. I have had the car for 10 months. I bought it off a work colleague who only did short journeys. I now do 50miles a day motorway but don't tend to thrash it (chance would be a fine thing always in heavy traffic!) I'm happy to get the spanners out and have everything on the list except oven cleaner. I can get some but I also have industrial de-greaser that I can try as well.
Now just got to find where everything I need to remove is located. I'm sure a Google search will help.

[Kusunagi]

Just an update guys. After all my efforts the car did not pass the emissions test. The garage said they cancelled the test as it blew to high so no point in carrying on. They then told me I need a new Dpf and injectors.I wasn't happy! So I took the car this morning to a local mot centre near me and paid for a new test to be done. It passed no problem with 1 advisory on a tyre. I should of listened to my friend who always tells me don't take the car to cheap mot places like the first place I went too.

[lizzard-t]

Glad you got a pass . it just shows the first garage's test equipment is either wrongly callibrated .or they are not purging it into fresh air long enough so that the sensors are not washed with the results on the last MOT or the filters require changing..what was the test results on the smoke test in the end ?

[Kusunagi]

He didn't give me the usual emissions paperwork just the mot pass certificate. I was so happy it passed I didn't notice it wasn't there. The other mot tester that cancelled the test said it blew 0.97. That's higher than the original fail of 0.80 after all the cleaning and driving like a maniac I have done it did supprise me. Maybe your right and there equipment isn't being purged. They do literally have one car in after another. They only charge £25 per mot so it's like a conveyor belt of cars going in.

[Dave1419]

Really should report that MOT station---they will do a check on the Mot station and see whats going on---looks like that they are not keeping their equipment maintained--sure you can do it online-----Dave

[Butt0ns]

Glad you got a pass . it just shows the first garage's test equipment is either wrongly callibrated .or they are not purging it into fresh air long enough so that the sensors are not washed with the results on the last MOT or the filters require changing..what was the test results on the smoke test in the end ?

A correctly functioning DPF will capture 99% of particulates. My last test on my '12 Biturbo with a limit of 1.5ppm was 0.02ppm on mileage of 160k
Testing rules;
 There must be at least one Pre-test blow out acceleration.
 There must be at least one free acceleration and six is the maximum allowed.
 Test is concluded and passed on less than three valid accelerations if reading is below 1.5 k m-1.
 Test is aborted and failed on first valid acceleration if reading exceeds 9.99 k m-1.
 Where no valid mean value has been achieved a ‘void’ result will be returned.
 In the case of HCV testing a gap of at least 10 seconds between the release of the accelerator and the prompt to carry out the next acceleration from idle is required.