Still smoking under heavy accelleration

I know there are a few threads on this and I think injectors could be the cause. I have tried some STP injector cleaner and no difference. Still unwilling to try my synergy 2 properly as when I do it smokes very very badly.

So I have serviced the car.

Air filter
Oil and oil filter
Fuel filter
BMW crankcase vortex breather
EGR blank
There are no leaks or holes in the pipe work

What could it be? Do I just need to put some Forte in?

I have no engine lights. I'm not sure if it is making normal power as it's the only one I have ever owned. It's a 2001 TD4 auto.

For what it's worth. When I did try the synergy I didn't feel that night and day feeling (setting 2). Hardly made any difference, if any?

It's black smoke too so something to do with fueling?

so something to do with fueling?

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too much fuel .. or not enough air

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could be that the MAF sensor is over-fueling it ..
amongst other possibilities ..

try disconnecting the MAf sensor 'n see what happens ..
at least it might rule out a faulty MAF as the cause

i.e. in theory .. if the MAF is ok .. then it should detect proper air-flow mass ..
so in the case of lack-of-air .. it should cause a reduction in fuel delivery ..

could be a faulty air-temp sensor ..
depending on year .. it's either a separate sensor in the post intercooler hose
or part of the maf electronics ..
( although that might effect idle as well .. given what a couple of LZ denizens have reported )

When I did try the synergy I didn't feel that night and day feeling (setting 2). Hardly made any difference, if any?

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should be a somewhat better response from the go-pedal ..
i.e. more immediate response .. when compared to 'stock' tuning ..
not so much waiting-for-something-to-happen

on setting '2' there won't be a huge difference in out-and-out power .. compared to 'stock'
still .. there is a difference in 'power' .. and torque ..
but mainly it's the response to the go-pedal that's most noticed

if .. with it turned 'off' .. there's immediate response ..
or like you say .. you can't tell any difference ..
sounds like the engine is already dumping a load of fuel in ..
black smoke when you floor the go-pedal would seem to confirm that ..
( btw: the ecu responds to rate of go-pedal movement as well as position )

would have thought there might be other symptoms .. like lumpy idle ..
if it were a naf injector or two ..
( don't know for sure .. just speculating )

Yeah, your making sense buddy and thanks for the PM. Never really thought about possible blockage too. The car runs like a dream, very stable idle etc. Fairly quiet too for a diesel.

is it possible that the EGR has filled the manifold full of black gunk stuff and as your driving your now forcing that though the engine and out the exhaust

only asking incase you maybe not though of it or maybe not that at all

Did it smoke before fitting the Synergy as the Synergy won't make the problem go away. It sounds like it could be the injectors are at fault, have you tried the leak back test. If you disconnect the MAF and the black smoke stops or decreases this could point to a faulty MAF.

try the pressure sensor, it might have dirty connections and if it's the case, the ecu will have a bad reading and start shoving in diesel like crazy (bad for pocket and bad for the lungs of the person behind )