ML 270 2003 MOT failure on emissions

[Money pit]

Dear All,
My 163k 2003 ML has failed MOT on emissions. I was advised to use some injector cleaner and take for an Italian tune up ( hammer up and down motorway) before re test. Took it in and it is slightly better BUT still failed. limit is 0.8, it was reading 0.85/0.86 on opacity test. Would welcome any top tips or advice on how else I could improve its emission or other things to check/change. Swirl valves have been removed, I changed oil, oil filter, diesel filter and air filter within last 4k miles, and used some STP injector cleaner. Car has only failed on emissions so its worth saving i reckon. thanks in advance

 

[M80]

Has MB stated yours to be 0.8 as cars pre July 2008 are 3?

 

[Taffy7hfa]

Hi, Your Truck is Euro 3

Euro 3 emissions standards (diesel)​

CO: 0.66g/km
HC + NOx: 0.56g/km
NOx: 0.50g/km
PM: 0.05g/km

Short duration Italian tune up wont work . however in my experience, if you can take it out for a 3 or 4 hour run at sustained motorway speeds around 2000 rpm, they generally seem to run quite a bit cleaner at the end of it, Euro 3 diesels will always smoke a bit under hard acceleration.

 

[Money pit]

Hi, Your Truck is Euro 3

Euro 3 emissions standards (diesel)​

CO: 0.66g/km
HC + NOx: 0.56g/km
NOx: 0.50g/km
PM: 0.05g/km

Short duration Italian tune up wont work . however in my experience, if you can take it out for a 3 or 4 hour run at sustained motorway speeds around 2000 rpm, they generally seem to run quite a bit cleaner at the end of it, Euro 3 diesels will always smoke a bit under hard acceleration.

thank you i will try that. have also been advised to try taking the air filter out ?

 

[mioba]

I would not run an engine without an air filter.
Try a premium fuel with a shot of redex.

Good luck and hope it flys through.

 

[Taffy7hfa]

Probably worth removing the egr and cleaning it out, they're usually pretty filthy.
As mioba says, running without an air filter is a bad idea.

 

[rifiki]

try Italian tune up.

 

[bladecrazy]

Is it tested to the limiter? i thought it would have been around 3.00 due to age.

 

[Money pit]

Is it tested to the limiter? i thought it would have been around 3.00 due to age.

I am informed by those in the know, due to the car displaying an opacity limit eg - 0.8 on the door pillar, then the tester needs to test to this limit. Without this information then a limit of either 1.5 or 3 would apply based on the cars age. Previous MOT's have been completed with a limit of 1.5 -3, with previous results from the car ranging from 0.4-0.6. so it appears i have car with a worsening emission and much stricter limit being enforced. I have researched , and add STP emission test cleaner, will add in some premium diesel and try again tomorrow. will let you know. thanks again.

 

[Blobcat]

I am informed by those in the know, due to the car displaying an opacity limit eg - 0.8 on the door pillar, then the tester needs to test to this limit. Without this information then a limit of either 1.5 or 3 would apply based on the cars age. Previous MOT's have been completed with a limit of 1.5 -3, with previous results from the car ranging from 0.4-0.6. so it appears i have car with a worsening emission and much stricter limit being enforced. I have researched , and add STP emission test cleaner, will add in some premium diesel and try again tomorrow. will let you know. thanks again.

It would be a terrible shame if that door sticker became damage or defaced...

 

[bladecrazy]

ha ha yes maybe the sticker could just fall off.

 

[Taffy7hfa]

I am informed by those in the know, due to the car displaying an opacity limit eg - 0.8 on the door pillar, then the tester needs to test to this limit. Without this information then a limit of either 1.5 or 3 would apply based on the cars age. Previous MOT's have been completed with a limit of 1.5 -3, with previous results from the car ranging from 0.4-0.6. so it appears i have car with a worsening emission and much stricter limit being enforced. I have researched , and add STP emission test cleaner, will add in some premium diesel and try again tomorrow. will let you know. thanks again.

Maybe try a different mot station