Campoll
Member
I have a 2007 D40 2.5ltr diesel just wondering if it blowing good amounts of black smoke is that normal? Is there a fix to it? Just needs thoughts? Thanks
D40 Blowing smoke
- Thread starter Campoll
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Black smoke is a sign of over fuelling which may also mean under-airing. Common causes:
1) Underspooling turbo - most commonly caused by faulty vac lines, but also fairly common is a failed solenoid. Rarely you'll hear about stuck vanes. Bearing failure might be a possibility especially if the turbo has been treated harshly - you'd have to check the amount of play in the impeller.
2) Dirty MAFS or air filter. MAFS can be damaged by an over-oiled K&N filter or by a failing paper filter (too much rain driving can dampen the filter and cause it to disintegrate - happened to me - allowing foreign particles (dust/insects) to land on the MAFS).
3) Boost loss. Split/cracked hoses, overtightened or undertightened charge air hoses or a cracked/damaged intercooler. Could also leak through the EGR if the valve is faulty or the EGR pipe is cracked (common).
4) Failing rail pressure sensor or turbo boost sensor. More often it's a loose/erratic connection on either. Less likely to be fuel pressure if the engine is running smoothly, but both can become erratic after pressure-washing the engine bay. Simple remedy is cleaning the terminals then remembering that the engine bay doesn't mind being a little dirty.
There are other things to consider but these are the easy ones to look at.
If the black smoke is only during acceleration but at normal driving it's fairly clear, you might be "normal". Blocking the EGR will reduce the amount of visible soot.
1) Underspooling turbo - most commonly caused by faulty vac lines, but also fairly common is a failed solenoid. Rarely you'll hear about stuck vanes. Bearing failure might be a possibility especially if the turbo has been treated harshly - you'd have to check the amount of play in the impeller.
2) Dirty MAFS or air filter. MAFS can be damaged by an over-oiled K&N filter or by a failing paper filter (too much rain driving can dampen the filter and cause it to disintegrate - happened to me - allowing foreign particles (dust/insects) to land on the MAFS).
3) Boost loss. Split/cracked hoses, overtightened or undertightened charge air hoses or a cracked/damaged intercooler. Could also leak through the EGR if the valve is faulty or the EGR pipe is cracked (common).
4) Failing rail pressure sensor or turbo boost sensor. More often it's a loose/erratic connection on either. Less likely to be fuel pressure if the engine is running smoothly, but both can become erratic after pressure-washing the engine bay. Simple remedy is cleaning the terminals then remembering that the engine bay doesn't mind being a little dirty.
There are other things to consider but these are the easy ones to look at.
If the black smoke is only during acceleration but at normal driving it's fairly clear, you might be "normal". Blocking the EGR will reduce the amount of visible soot.
