Engine breathing

[mcv]

Hi all,
Had a 120,000km service on my D22 2011 yesterday. All the general stuff carried out all ok.
I asked the mechanic to have a look at the reason why its blowing a lot of black smoke in all gears.
He said that the top might be full of carbon etc and to use a product called "engine conditioner" from repco. He said to give a good squirt of it down the air inlet pipe whilst the engine was hot and this would de carbon it.

Any one else used this product and did it make any difference? or is there a better one out there?

Your comments please

Btw d22 hasn't had the EGR blocked off yet...will this weekend

Many thanks Richard

 

[Old.Tony]

Oh dear. Sounds like a mechanic who hasn't spent a lot of time around diesels!

Black smoke is a sign of overfuelling. That's a very specific term: it means too much fuel for the amount of air in the motor. This means:

* it could be the RIGHT amount of fuel accompanied by an air restriction, or a lack of performance from the turbocharger, or too much EGR or blow-by gas, reducing the amount of air available to the engine for combustion; OR

* it could be the right amount of air, with an injector problem (dirty/sticking), fuel pressure sensing problem (faulty sensor, loose connection), a timing problem (CAS loose/faulty or interfered by debris).

The very first step is to block the EGR. It's not needed and causes black smoke.

After that, it's a matter of checking everything over. Pull the air filter and inspect it for dirt and moisture (a wet air filter doesn't work well). Check the turbocharger for smooth operation with no shaft wobble. Remove and clean the intercooler if it has one.

After those basic (cheap) steps, you can look at other possible causes.

 

[mcv]

Hi Tony,

Fitted the blanking plate today and gave it a quick run.
Seems most of the smoke has gone now..Excellent
Thanks