Help please ! - 2011 Ford S-Max 2.2 TDCi issues

[ourchris]

Hello all - I don't post often, so please bear with me....

I have ongoing issue with my S-Max. It's an issue with white smoke from the exhausts - accompanied by a burning smell in the cabin.

The car will drive normally - with no smoke or issues - no lack of performance during normal running, stationary or under load - and no smoke. The car has been on a number of long distance trips as well as town driving.

Periodically, there will be a burning smell in the cabin - accompanied by plumes of white smoke out of the exhausts. This cannot not be predicted or replicated - and appears to mainly happen following a period at idle. If you turn the engine off while this is happening - and then restart the car the smoke stops.

I then get an engine light - and the fault code P2463 (which tells me that the DPF is full). The car does not go into limp mode, there is no tail off in performance or fuel economy BUT all burning smells in the cabin and smoke from the exhausts stop completely!

My friends at Ford have at best useless in diagnosis so far - and pretty much every time is goes in suggest another thing to change, or tell me to change the oil, stop driving the car in town, and send me on my way with a DPF regen. So far I have changed.

All four fuel injectors - I knew that this needed doing as the car has 150k on it. This lead, as you can imagine to a noticeable increase in fuel economy.
Lambda sensor (heated oxygen sensor bank 1).
Differential pressure sensor.
Fuel vaporiser.
DPF.

Fortunately I have done this myself so I have a reasonably intact wallet - but I am still looking for a fix. I know that I should probably give up on it, but childishly I am now at war with the car, and I have to win.

Any thoughts anyone please ?

[GreenV8S]

The smell and heat corresponds to a DPF regen. This is your car's attempt to clean the DPF. The car will only try to do this when specific criteria are met. If it doesn't meet those criteria often enough, or the regen cannot be completed or is ineffective at cleaning the DPF then the DPF will eventually block. The fault codes you report suggest this may be happening.

I suggest you find out what the exact criteria are for your car to carry out the regen and make sure it completes.

If the car has to keep aborting regens and then re-trying them later this involves running very rich which will lead to the oil being contaminated with fuel - this is why you were advised to change the oil.

There are various fault conditions which can prevent a regen from occurring or prevent it from being effective, so if your DPF keeps getting blocked you should look for other problems causing this. If your car is working as designed and given the chance to carry out regens when necessary then the DPF should be fine for at least many tens of thousands of miles, and probably for the life of the vehicle.

[E-bmw]

Is the correct answer, in other words, perhaps the garage are telling the truth.

[ourchris]

I'd love to believe that, but -

Visit number 1.... Change oil, DPF regen - less than 100 miles later, same issue
Visit number 2.... I pointed out that they already changed the oil. Okay, it's not the oil, it's the lambda sensor. Forced regen by Ford, changed the sensor
Visit number 3.... It must be the fuel vaporiser. Changed it. Same issue
Visit number 4..... Right. It's the DPF and the differential pressure sensor. Changed them.

I still have the same issue, and all its done is make me not trust Ford now, as they appear to be not identifying root cause - I'd rather them tell me that they don't know what's wrong TBH.

I'd really appreciate some help with this one !!

Thanks

[GreenV8S]

You can check the differential pressure sensor by measuring the actual differential pressure. If the differential pressure is within limits, the DPF is fine. If not, it's blocked. In that case you need to clean or replace it, and discover why it became blocked. The possible reasons are driver error, or a fault elsewhere (exhaust leak, stuck EGR etc). Your garage will already know all this and should be diagnosing it for you.

ETA: the symptoms of heat, smoke and an engine fault lamp when you turn the engine off while this happens is the normal expected behaviour of a DPF regen. Typically these would happen every 500 miles or so and take a few minutes. If they are happening much more frequently than that or lasting much longer, you may have a problem as described previously.

Edited by GreenV8S on Friday 22 March 21:24

[ourchris]

Thanks V8S.... In summary, I think I should change garage. As per your reply they should be diagnosing this rather than blindly recommending I change parts to see what happens.

[E-bmw]

Also as per the original answer you need to find out what are the requirements/constraints of the car performing a DPF regen & make sure you do this regularly.

The worst thing for DPFs is short journeys & aborted regen routines.

This could be why you are getting repeated issues, if so you have been poorly advised & as a result have the wrong car.

[ourchris]

Thanks E-bm

The car is primarily used for long distances - it's a motorised suitcase for the family in essence.

[elnokur77]

Dear Ourchris!

I have the same issue with 2011 S-Max 2.2 Tdci. Did your found the rootcause of you problem?