MGT

Active Member
Full Member
Common fault I believe - black smoke under hard acceleration - but I can't isolate the cause.
I have felt around the hoses for leaks and can't detect any, and I also pulled the hoses off a spare Freelander which had no such problem and fitted them.
Along with the black smoke under hard acceleration I can hear a whine or whistle, which makes me think there could still be a leak.

I'm still very new at this, so forgive the daft question, but is there a fourth rubber hose at the back of the engine bay coming out of the turbo that links it to the alloy pipe that goes to the front of the engine? And if so, does this often go? This I have not yet replaced.

Also, if the vacuum hose from the boost control solenoid (I think it is) is perished, would that impact on the flow of air to the combustion chamber?

Lastly, the black smoke seems to have started after I shoved a fair bit of injector cleaner through it, but surely I cannot be burning this off still after more than a month driving it?
Anything obvious I might have missed?
I have sprayed the MAF sensor, although it looked pristine and I unblocked the MAP sensor.
Could that MAP sensor have blocked up again real quick. and could that explain the black smoke by itself?
 
if the vacuum hose from the boost control solenoid (I think it is) is perished, would that impact on the flow of air to the combustion chamber?
if it's leaking .. it will effect the turbo vane operation ..
which in turn will effect air flow to the intake

a fourth rubber hose at the back of the engine bay coming out of the turbo that links it to the alloy pipe that goes to the front of the engine? And if so, does this often go?
they have been known to delaminate on the inside 'n causing a blockage ..
though .. not be a very common occurrence on these pages ..
i suppose .. they could leak if damaged / aged .. etc .. not unheard of ..

```````````````````````````````````````````````````````````````````````````````````````````````````````
 
if it's leaking .. it will effect the turbo vane operation ..
which in turn will effect air flow to the intake


they have been known to delaminate on the inside 'n causing a blockage ..
though .. not be a very common occurrence on these pages ..
i suppose .. they could leak if damaged / aged .. etc .. not unheard of ..

```````````````````````````````````````````````````````````````````````````````````````````````````````
Right, thanks. I will replace both and see what happens. I understand that something is preventing a boost in air intake as I increase the flow of diesel. Just seem to be so many variables. I'd give quite a lot now to have a car without a turbo.
 
That vacuum hose, then, does that operate the waste gate inside the turbo or does it link directly to the performance of the vanes?
I watched a video which showed how to increase boost, and that seemed to work by preventing the waste gate opening at the specified setting.
If its the vacuum hose then I would have thought - thinking about it - that a split pipe ought to increase boost rather than reduce it because waste gate won't open.
Just trying to think it through.
 
What about turbo cleaner spray? If vanes all clogged up with crap then maybe they cannot produce enough boost when demand is high. Anyone use that spray for this?
 
Another thought is that in order to push more compressed out the turbo has to draw more uncompressed air in, and that has to go through the air filter. It is fairly new, so wouldn't have thought a dirty filter is responsible, but maybe the brand has an impact. Is it possible that a cheap ****e air filter is responsible?
 
That vacuum hose, then, does that operate the waste gate inside the turbo or does it link directly to the performance of the vanes?
I watched a video which showed how to increase boost, and that seemed to work by preventing the waste gate opening at the specified setting.
If its the vacuum hose then I would have thought - thinking about it - that a split pipe ought to increase boost rather than reduce it because waste gate won't open.
Just trying to think it through.

Right, no need to answer that (if anyone was going to) - just read that the vacuum pipe controls the waste gate opening and closing to regulate the amount of exhaust gas coming in to compress the air. Obviously if pipe is split and vacuum compromised the gate won't open and you won't get boost. Article suggested checking that pipe for splits.
If that is bollocks please let me know, but it makes sense.
 
just read that the vacuum pipe controls the waste gate opening and closing to regulate the amount of exhaust gas coming in to compress the air.
yeah .. the vacuum solenoid controls the vacuum associated with the mechanism that moves the turbo vanes
( there's no 'wastegate' .. so to speak .. on the fl1/td4 turbo ..
( just a means of moving the vanes as the ecu determines
( unless the turbo has been replaced with another type at some-stage 'n the vac system messed with
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 
yeah .. the vacuum solenoid controls the vacuum associated with the mechanism that moves the turbo vanes
( there's no 'wastegate' .. so to speak .. on the fl1/td4 turbo ..
( just a means of moving the vanes as the ecu determines
( unless the turbo has been replaced with another type at some-stage 'n the vac system messed with
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Thanks.
 
When did you spray the MAF sensor before the smoke or after? what was it sprayed with? 99.9 when a MAF is sprayed it will damage it rather than do it any good, is the EGR clean or all gunked up with black tar? did you remove the manifold when you cleaned the MAP sensor?
 
When did you spray the MAF sensor before the smoke or after? what was it sprayed with? 99.9 when a MAF is sprayed it will damage it rather than do it any good, is the EGR clean or all gunked up with black tar? did you remove the manifold when you cleaned the MAP sensor?

Was smoking before sprayed MAF sensor - did it with some contact cleaner. EGR fairly clean - I degunked it and checked it was working. Took manifold off to clear some of crap out of it and did MAP sensor at same time - although all I did with that was spray the contacts and use a pin to clear the blockage in the nozzle.
I've got a hunch it may be the vacuum hose(s). I'm going out to check again in a minute and I think possibly someone has used fuel line for the link to the turbo rather than vacuum pipe.
On that note, I cannot find info on what diameter pipe is supposed to be used. I'm guessing 3/3.2 or 4mm. Anyone know?
 
I'm guessing 3/3.2 or 4mm
4mm

and use a pin to clear the blockage in the nozzle.
need to be careful doing that .. there's a diaphragm inside the map sensor ..

EGR fairly clean - I degunked it and checked it was working.
be worth doing the 'egr-delete' mod ..
no gunking up of the intake .. 'n slightly better mpg
( and so far no reports of mot issues )

'n just in case your not familiar with turbos
( and the owner's manual is missing )
change engine oil regularly ..
be sure the crankcase-vent is working as it should
and idle the engine for a bit before shutdown
( to cool down the turbo so as the oil does not coke-up
( and disrupt a cooling oil supply to the turbo bearings

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 
Last edited:
4mm


need to be careful doing that .. there's a diaphragm inside the map sensor ..


be worth doing the 'egr-delete' mod ..
no gunking up of the intake .. 'n slightly better mpg
( and so far no reports of mot issues )

'n just in case your not familiar with turbos
( and the owner's manual is missing )
change engine oil regularly ..
be sure the crankcase-vent is working as it should
and idle the engine for a bit before shutdown
( to cool down the turbo so as the oil does not coke-up
( and disrupt a cooling oil supply to the turbo bearings

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Thanks - have heard about the idle before but keep forgetting. Will have to force myself to make that a habit.
I did the crankcase breather assembly recently - whole top half not just sponge filter.
The only thing I haven't done is change the turbo vent filter, and it is a bit mucky. I will get one of those.

just finished changing the vacuum hoses and while it feels a bit more sprightly I still get the cloud of black smoke when I ramp it in second.
Getting a smoke test done next week which might yield a result.
Thanks for the help.
 
I wonder if the maf sensor is dodgy? The Mass Air Flow sensor is essentially a hotwire air flow meter, electrical current heats a wire suspended in the air intake tract, air flowing over it cools it, resistance changes with temperature and the ecu sees the voltage in and out and works out the airflow based on how much air it would take to cool the sensor to a point where it generates these signals. Then the ECU applies that reading to its maps and controls the injectors accordingly. The bosch units fitted to these cars deteriorates over time, generating running issues, "Rover Ron" makes a box called a synergy 2 that compensates for a bad maf signal, and he has found a physically interchangeable maf from pierburgh that has different electrical characteristics, but doesnt degrade like the bosch one, accordingly he has a toggle switch on his box to run the pierburgh maf on our cars. Might be worth going down that route? If nothing else you could adjust the synergy to lean it out a bit and stop the black smoke?
 
I wonder if the maf sensor is dodgy? The Mass Air Flow sensor is essentially a hotwire air flow meter, electrical current heats a wire suspended in the air intake tract, air flowing over it cools it, resistance changes with temperature and the ecu sees the voltage in and out and works out the airflow based on how much air it would take to cool the sensor to a point where it generates these signals. Then the ECU applies that reading to its maps and controls the injectors accordingly. The bosch units fitted to these cars deteriorates over time, generating running issues, "Rover Ron" makes a box called a synergy 2 that compensates for a bad maf signal, and he has found a physically interchangeable maf from pierburgh that has different electrical characteristics, but doesnt degrade like the bosch one, accordingly he has a toggle switch on his box to run the pierburgh maf on our cars. Might be worth going down that route? If nothing else you could adjust the synergy to lean it out a bit and stop the black smoke?

I've heard of the Ron box. Its a thought. I might nick the one off the donor car first to see if it makes a difference. Tbh I assumed because it looked clean it would be ok, but seems not. Thanks for the tip.
Thing is, I only get the smoke when I floor the pedal - normal acceleration is ok. That just feels like the turbo isn't able to supply the extra air needed for the increase in fuel in extreme cases. The exhaust does still smell a bit of diesel, although it is al lot better than it was. I know it's running rich though because fuel consumption is down from where it ought to be.
probably find it will be the last thing I look for, but the good thing is when I do nail it all the other bits will have been done.
Im still a bit surprised by the difference the proper vacuum hose has made. While it hasn't cured the black smoke I've got a shed load more latitude in the gears. The old pipe was fuel pipe and had deteriorated so much the walls must have been collapsing under the vacuum. all part of a learning curve for me, finding it very interesting.
I will do the MAF replacement at the weekend and report back - thanks again.
 
I've heard of the Ron box. Its a thought. I might nick the one off the donor car first to see if it makes a difference.

I've just removed my Synergy as I'm preparing the FL1 for sale. I was shocked at the lack of performance without it fitted. However the aftermarket MAF on it was rubbish too, making it feel even worse. I've refitted fitted the original Bosch MAF, and it's better, but still nothing like as good while the Synergy is active.
 
I've just removed my Synergy as I'm preparing the FL1 for sale. I was shocked at the lack of performance without it fitted. However the aftermarket MAF on it was rubbish too, making it feel even worse. I've refitted fitted the original Bosch MAF, and it's better, but still nothing like as good while the Synergy is active.

Thanks for that. Going to have a look at one now.
 
Its not a huge amount of money for something that has such good reviews. Good news is that I did a leak off test earlier so I know its not the injectors. That was a surprise, I was expecting the worst.
Also put in a new air filter and a crankcase breather replacement cyclone.

But it still doesn't feel like the turbo is engaging properly. There's the short rubber boost pipe that attaches to the turbo - that felt a bit flimsy even if I couldn't;t feel any splits. It looks like a bugger to get to though.
.
 

Similar threads