Hi guys new to this group I find it very helpful so hopefully yous could help sort out my problem I’ve an 07 d40 automatic and lately it gotten very smoky black and getting really slow it seems like a lot of effort to get it to 100km. So the egr is blanked off I’ve cleaned the MAF new air filter new fuel filter and I’ve just changed the BCS and nothing is working hopefully some can point me in the right direction thanks a million
Slow and black smoke
- Thread starter Aero mac
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Next target is the vac hoses themselves. The last time I changed them, I bought 3mm inside-diameter hose from Supercheap auto (3 metres required, cost me $15 all up). I went back to get some more and they only have 2.5mm ID hose, so I haven't done anything yet ... I'll probably ask my local mechanic to see if he's got any around the place.
A vacuum leak will cause the turbo to not respond as well (if at all), so the engine won't be getting enough air, which means it won't have enough air to burn the fuel completely = black smoke and loss of power.
Of course, it could be a failing turbo, but let's not replace the $1500 item when it might just be a $15 item!
There are two other "leak" possibilities that could do this. A boost leak - between the turbo and the intake manifold - means you're losing some of that pressurised air and causing the same result as above. You should be able to hear this though, but it will also be visible as a black oily emission around the leak. It might also be an exhaust leak - usually very loud, and with black sooty emissions around it. Check the EGR pipe, particularly the concertina area which is fragile. On mine, the gasket between the exhaust manifold and turbo let go, causing a screeching sound whenever the pressure got high enough.
Poor injection quality might also do it (tried injector cleaner?) but you don't hear of this a lot.
Next target is the vac hoses themselves. The last time I changed them, I bought 3mm inside-diameter hose from Supercheap auto (3 metres required, cost me $15 all up). I went back to get some more and they only have 2.5mm ID hose, so I haven't done anything yet ... I'll probably ask my local mechanic to see if he's got any around the place.
A vacuum leak will cause the turbo to not respond as well (if at all), so the engine won't be getting enough air, which means it won't have enough air to burn the fuel completely = black smoke and loss of power.
Of course, it could be a failing turbo, but let's not replace the $1500 item when it might just be a $15 item!
There are two other "leak" possibilities that could do this. A boost leak - between the turbo and the intake manifold - means you're losing some of that pressurised air and causing the same result as above. You should be able to hear this though, but it will also be visible as a black oily emission around the leak. It might also be an exhaust leak - usually very loud, and with black sooty emissions around it. Check the EGR pipe, particularly the concertina area which is fragile. On mine, the gasket between the exhaust manifold and turbo let go, causing a screeching sound whenever the pressure got high enough.
Poor injection quality might also do it (tried injector cleaner?) but you don't hear of this a lot.
hi i have the same issue, been chasing my tail for weeks now and emptied my wallet, done all the usual suspects, plus some more items that old Tony pointed out but still no joy, have put it down as the turbo so just the time now to take it off and replace and then see what happens ! the only thing i havent looked at is the fuel rail sensor, i also have a DP chip installed removed that still no luck.
with black smoke its either running to rich or way out of timing, or really poor injection quality, or way to much egr.
even with turbo not running it should be injecting the correct amount of fuel for the airflow and throttle.
so either its miss reading the air flow (map sensor or air leak after the map sensor including before the turbo), or injecting way more fuel than it should.
a common issue is not resetting the fuel data after changing fuel filter.
if its getting low power and black smoke, it can be a major air leak or it can be worn injectors or incorrect timing. i would be checking the timing chain.
even with turbo not running it should be injecting the correct amount of fuel for the airflow and throttle.
so either its miss reading the air flow (map sensor or air leak after the map sensor including before the turbo), or injecting way more fuel than it should.
a common issue is not resetting the fuel data after changing fuel filter.
if its getting low power and black smoke, it can be a major air leak or it can be worn injectors or incorrect timing. i would be checking the timing chain.
Thanks for all the info I’m going to get stuck into it now and check all them small vacuum pipes and hopefully it will be one of them but like TCN said in his post mine is the same on hills just loses all power but great going down so hopefully I’ll find something I’ll keep you posted on my progress
Problem solved we have boost again and no black smoke running very smooth now so checked all the vacuum hoses and it was the small one on the driver’s side had a wee crack in it so replaced it and job done. Thanks a million to all who pointed me in the right direction yous are legends 
Sorry about this but after getting my boost back I’ve find a new problem I was on my way home from work and needed to pass a truck out so I put the foot down to get passed great power till I hit about 3500 rpm and then it went into limp mode so pulled over turned it off started again and power was back would anyone have any ideas why this is happening also got it plugged in today there was a fault staying on it something to do with the injectors the lad didn’t know what it ment and said it would be fine I really hope it is not a full set of injectors any advice pls
Went through a bit of this with the daughter's 07 d40 - her turbo was on the verge of going, vacuum hoses falling apart and we lucked out with a dud from new boost control solenoid while on the journey. Once everything was replaced we had a limp mode event that left behind a low fuel pressure error in the log. Has been purring like a kitten in the 3 months since the error was cleared, so I probably wouldn't stress about it unless you find it recurs. I put it down to the ecu resetting all its data points once everything was working as it should and getting all confused.
