D5 (2005 on) Smoke and misfire

[stroudD5]

Afternoon all, I am on my second D% engined Volvo and they have previously been fantastic. However I now have a problem I am struggling to resolve. My )5 V70 D5 manual has taken to emitting black smoke acompanied by a light misfire on light throttle that if revved hard clears. I code reader showed a MAF problem so that was replaced, but no difference. Had a recent full service, and now shows no fault codes. I cant find any split hoses or hear any strange noises. Does the team think injector cleaning or is there something else to look at? Please help

[skyship007]

Originally Posted by stroudD5

Afternoon all, I am on my second D% engined Volvo and they have previously been fantastic. However I now have a problem I am struggling to resolve. My )5 V70 D5 manual has taken to emitting black smoke acompanied by a light misfire on light throttle that if revved hard clears. I code reader showed a MAF problem so that was replaced, but no difference. Had a recent full service, and now shows no fault codes. I cant find any split hoses or hear any strange noises. Does the team think injector cleaning or is there something else to look at? Please help

The misfire part sounds more like a turbo issue than injectors, although a bad HP injection pump can cause the symptoms described.

It's always a good idea to use a direct feed injection system cleaner like Liqui Moly Diesel Purge when changing the fuel filter element, as all you need to do is fill up the housing with the cleaner. If you do that, make sure to read the instructions about varying the idle RPM whilst the cleaner is in use.

When did you last clean the air intake. It should be done when the EGR is cleaned, but if it has been ignored that can eventually result in a rich mixture in the same way as a blocked air filter.