MOT failed：exhaust emissions exceed manufacturer's specified limit

cherry2017

ford mondeo mk4 2009,
how can I pass it again? thanks

marlot

What are the readings?  Was the car properly warm?

cherry2017

just bought this , hope it can help

Laser 60370 Cataclean Diesel 500ml - CAT002

Ebe_Scrooge

cherry2017 said:

just bought this , hope it can help

Laser 60370 Cataclean Diesel 500ml - CAT002

Snake oil.

A half-decent mechanic should be able to diagnose the problem.  A common problem is a malfunctioning sensor (of which there are several), usually very simple and cheap to replace.  As regards to your question "how can I pass it again", do you have a trusted mechanic you use?  For someone who knows what they're doing, emissions problems are very often quite simple and cheap to remedy.  Yes, it might be the DPF that's buggered, which can be expensive - but there are loads of other things to check first.

facade

The "usual" advice is to add the snake oil now you've bought it, and take the car for a good half hour high speed run on a fast road, using plenty of revs on the way to the retest.  If it still fails you will have to get someone to diagnose the problem, but it is often just residue in the exhaust pipe from short low speed journeys.

cherry2017

facade said:

The "usual" advice is to add the snake oil now you've bought it, and take the car for a good half hour high speed run on a fast road, using plenty of revs on the way to the retest.  If it still fails you will have to get someone to diagnose the problem, but it is often just residue in the exhaust pipe from short low speed journeys.

THANKS. I will let the snake bite it first,
then, btw, if I leave the car in my private drive way, and I don't drive it, how about my car insurance, or any other problem before I fixed it?

DB1904

cherry2017 said:

facade said:

The "usual" advice is to add the snake oil now you've bought it, and take the car for a good half hour high speed run on a fast road, using plenty of revs on the way to the retest.  If it still fails you will have to get someone to diagnose the problem, but it is often just residue in the exhaust pipe from short low speed journeys.

THANKS. I will let the snake bite it first,
then, btw, if I leave the car in my private drive way, and I don't drive it, how about my car insurance, or any other problem before I fixed it?

What does your policy say? If it were to be stolen don't expect a full payout if it's not got an mot?

What time of the day was your test and how far had you driven it to the garage?

Ectophile

DB1904 said:

cherry2017 said:

facade said:

The "usual" advice is to add the snake oil now you've bought it, and take the car for a good half hour high speed run on a fast road, using plenty of revs on the way to the retest.  If it still fails you will have to get someone to diagnose the problem, but it is often just residue in the exhaust pipe from short low speed journeys.

THANKS. I will let the snake bite it first,
then, btw, if I leave the car in my private drive way, and I don't drive it, how about my car insurance, or any other problem before I fixed it?

What does your policy say? If it were to be stolen don't expect a full payout if it's not got an mot?

What time of the day was your test and how far had you driven it to the garage?

They will pay out the value of a car that's failed an MOT.  Which won't be much more than scrap value.  Possibly nothing, if the policy has a large excess.

SiliconChip

cherry2017 said:

ford mondeo mk4 2009,
how can I pass it again? thanks

Surely the only answer we can give is to fix whatever is causing the high emission reading. Without knowing what engine or even fuel it is, and what reading is high, it's impossible to say anything more specific.

When my own car failed with a Lambda reading of 1.095 (Fiesta 1.0 Ecoboost petrol) it turned out to be because of an air leak on the inlet manifold, replacing a worn tube brought the reading down to 1.008, within the limits again.

DB1904

SiliconChip said:

cherry2017 said:

ford mondeo mk4 2009,
how can I pass it again? thanks

Surely the only answer we can give is to fix whatever is causing the high emission reading. Without knowing what engine or even fuel it is, and what reading is high, it's impossible to say anything more specific.

When my own car failed with a Lambda reading of 1.095 (Fiesta 1.0 Ecoboost petrol) it turned out to be because of an air leak on the inlet manifold, replacing a worn tube brought the reading down to 1.008, within the limits again.

One would hope it's not a petrol engine. 

Bigwheels1111

A fuel cleaner and a good spanking should do the trick.
Ive had many diesel’s in the last 25 years.
My Peugeot 5008 is a 1.6 bluehdi with 15,000 miles.
Just had my 3rd mot, it’s allowed a reading of 0.50.
1st year 0.01 2nd 0.02 3rd 0.01.

My old diesels all had 100,000 plus miles, A day before mot I would go to a motorway and hammer 
it up the on ramp and get to 70 ish and drop down a gear or 2.
Keep it at 3000 rpm for 10 minutes.
Turn round and do it on the way back.
If it did not pass after that I would dump the car.
Never had one fail after a good spanking though.