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Mjet Low boost + smoke

I know there are many threads containing fixes for this, however ive tried everything i can think of but to still not found the problem.

car is 156 Mjet 140BHP 16v with an alfatune map to 175BHp (done a year ago)

Its always been smokey, before the map and after the map , gus blamed the injectors not closing if i remember correctly.

anyway, the low down whoosh boost has gone, boost is coming in at 2500rpm, but the low down turbo spooling isnt there.

done this list so far: -

clean egr, checked it moves with FES
clean map
changed AFM for a new cheap ebay item, no difference but did get repeated error code 1238 sometimes, so removed for orginal boash one
removed lower turbo to intercooler hose, no splits, cracks, looks fine but oily as hell, turbo compressor wheel looks dry
checked intercooler to manifold hose, again looks fine
checked booster controller with FES, can hear it clicking, checked hoses for boost controller down to turbo

can move turbo vane do dar that the boost controller should move with fingers
removed ERG valve again and inserted blanking plate, makes no difference and no MCSF coming up
ECU reset done twice now

Stumped.

In FES the desired air quality and the actual pretty much agree with each other when the engine is reved, but the desired boost pressure and the actual boost pressure dont, actual boost is always 100 - 200 mm lower and seams to top out around 1100 mm

I have a new lower turbo hose from autolusso to fit tonight, but thats not it.
only other think i can think of is the intercooler is leaking

any ideas ?
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I'd go check the intercooler for air leaks then change the MAP sensor

just had a thought........ maybe leaking injector? doubt it but its easy to check air getting past it
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i would still be tempted to blame the EGR. suprised you didnt have it deleted in the map.

unless it is utterly spotless you can clean it but will still stick open or not open far enough.

if you've got a blanking plate try taking the EGR off, bolting the blanking plate to the EGR and fill it with degreasing / carb cleaner type spray. once full open the valve with fingers and top up. leave it to soak for a good few mins and then work it like hell by hand opening n closing it.

that will make sure its clean as hell.
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I suspect a faulty MAP sensor. It may be sending false readings, telling the ECU that there's boost when there isn't.

Any chance you could swap yours with a friends then compare how the car feels?
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thanks for the replies

the injectors have all been out recently for new copper sealing washers, took 13 hours for my mech to get them out, hence i can not afford for the car to go to a garage again.

the erg is blanked off, no matter what it does it can not leak the boost away, but MCSF has come on again now so the ecu knows its blocked off i guess. I didnt realize that the egr could be deleted in the remap, first diesel car, and last diesel car.

theres a second hand intercooler on the bay so i could try that i guess, then the map sensor
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thanks for the replies

the injectors have all been out recently for new copper sealing washers, took 13 hours for my mech to get them out, hence i can not afford for the car to go to a garage again.

the erg is blanked off, no matter what it does it can not leak the boost away, but MCSF has come on again now so the ecu knows its blocked off i guess. I didnt realize that the egr could be deleted in the remap, first diesel car, and last diesel car.

theres a second hand intercooler on the bay so i could try that i guess, then the map sensor
The 16v mJTD can not be completely blanked off, if will detect it and the light will come on.

You have to install a "restrictor plate". Its basically and blanking plate with an 8mm hole in it so you could alter your own blanking plate. The 8mm hole allows just enough exhaust crap through to stop the light coming on ..
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no offence mate but 13 hrs to get four injectors out!!! I'd be looking at using someone else. If I took 13 hrs to remove four injectors i'd be too embarrassed to charge my customers...

I'd go with Shadey, MAP would be good bet, and as he said again, if anyone near you has a working one see if it makes a difference..
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(Post Link) post #8 of 23 Old 04-05-12 Thread Starter
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this guy fixes intergrales and builds rally cars for a living, no muppet... and i wasnt charged for 13 hours, broke two injector pullers and in the end used a slide hammer to get them out, im just glad i didnt try to do it myself !

MAP is next thanks
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No wonder he had problems, injectors screw in don't they?

Edit.
No they don't, see attached pic.
Attached Images
File Type: jpg $(KGrHqJ,!iwE8MUmb!kUBPUSnIIkyQ~~60_12.JPG (14.3 KB, 15 views)
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(Post Link) post #10 of 23 Old 04-05-12 Thread Starter
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sod it... booked it in

fed up of the bloody thing
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Quote:
Originally Posted by Cream View Post
I know there are many threads containing fixes for this, however ive tried everything i can think of but to still not found the problem.

car is 156 Mjet 140BHP 16v with an alfatune map to 175BHp (done a year ago)

Its always been smokey, before the map and after the map , gus blamed the injectors not closing if i remember correctly.

anyway, the low down whoosh boost has gone, boost is coming in at 2500rpm, but the low down turbo spooling isnt there.

done this list so far: -

clean egr, checked it moves with FES
clean map
changed AFM for a new cheap ebay item, no difference but did get repeated error code 1238 sometimes, so removed for orginal boash one
removed lower turbo to intercooler hose, no splits, cracks, looks fine but oily as hell, turbo compressor wheel looks dry
checked intercooler to manifold hose, again looks fine
checked booster controller with FES, can hear it clicking, checked hoses for boost controller down to turbo

can move turbo vane do dar that the boost controller should move with fingers
removed ERG valve again and inserted blanking plate, makes no difference and no MCSF coming up
ECU reset done twice now

Stumped.

In FES the desired air quality and the actual pretty much agree with each other when the engine is reved, but the desired boost pressure and the actual boost pressure dont, actual boost is always 100 - 200 mm lower and seams to top out around 1100 mm

I have a new lower turbo hose from autolusso to fit tonight, but thats not it.
only other think i can think of is the intercooler is leaking

any ideas ?
have you taken off small bore rubber pipes off turbo actuator and one off engine to BCS and checked them properly?
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re read, you say boost 100-100mm and 1100mm do you mean actual air at maf?if mass air 100-200mg low doesn't sound too bad, and 1100mg is top figure at what boost at what revs? if boost in mb you've got massive hole somewhere or duff map sensor.
A log of requested boost, actual boost, vnt%, revs would help.
Vnt valve operating doesn't really tell wether vnt actuator is getting full vac.
With engine idling vnt is 75% on fes, vnt arm pulled to stop screw.if you pull vac pipe off actuator lever should go fully open, then put pipe back on to see how quick it pulls in again.
Travel of actuator rod in/out is approx 9-10mm.
i disconnected pipe and drove up the road to test something else, sounded different( deeper ) and drove like there was no turbo at all.
I'm guessing your talking about Howard/allitalia. He did my q2/clutch job, good bloke.

heres a vid operating on bench this is only half travel -300mb vac or so -600mb is needed to pull it to stop screw(max spool)
http://youtu.be/sG-Nl1eEyCE
check if your intercooler is same as stilo if so pm me!also map sensor i have a spare im not 100% about as i got low boost 16-17psi but your welcome to try it.

Last edited by sussexa; 08-05-12 at 12:26.
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have you taken off small bore rubber pipes off turbo actuator and one off engine to BCS and checked them properly?
I'd replace them with Silicone Rubber tubing regardless of what they looked like, even a very small leak can cause chaos.
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(Post Link) post #14 of 23 Old 09-05-12 Thread Starter
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Ok so this weekend the car was worse than the last two weeks, feels like 50BHP and no boost at any revs now. previously i was getting boost at 2500rpm.

i know it cannot be the EGR valve since if i blank it off, the turbo still doesent spool up, i realise that MCSF will come up with the EGR blanked, but it does test wether the issue is there.

since fitting one of shadymans EGR ristrictor plates with a 7mm hole there is a lot less smoke !

new lower turbo hose fitted, checked intercooler hose, ok

so once again i pull the pipes of the boost controlled solinoid, the lower one going to the actuator - i can suck on it and see the actuator move, and i can hold it fully open with my tongue in the pipe, so it can not be this section

the small hose from the metal pipe to the BCS, which i checked would hold vacumm last week, now will not !!! with a magnifying glass i can see what look like splits from someone using pliers to pull the pipe off

to be fair the pipe looks perished both ends, so i cut 20mm of each end, but have to warm the pipe in hot water to get it back on the metal pipe, i guess its flared one end.

drive car - huge boost everywhere, god dammit

i can remeber driving to liverpool 4 weeks ago, there was nothing wrong then, so in the space of two weeks ive lost low down boost and finally all boost just to a tiny split in this pipe

will order some 3mm silicone, or is it 5mm of ebay and replace the lot

thanks guys
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Just found this thread, I admire your perseverance and I'm glad to see you found the fault, sounds like a right 'mare though... Bloody wiesels...
 
(Post Link) post #16 of 23 Old 09-05-12 Thread Starter
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Just found this thread, I admire your perseverance and I'm glad to see you found the fault, sounds like a right 'mare though... Bloody wiesels...
anit that the truth, anybody that thinks wiesels are cheap to run needs a tap on the head, never had a car like this one - im a laughing stock in work - out there every week trying to fix it at lunch time
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Ok so this weekend the car was worse than the last two weeks, feels like 50BHP and no boost at any revs now. previously i was getting boost at 2500rpm.

i know it cannot be the EGR valve since if i blank it off, the turbo still doesent spool up, i realise that MCSF will come up with the EGR blanked, but it does test wether the issue is there.

since fitting one of shadymans EGR ristrictor plates with a 7mm hole there is a lot less smoke !

new lower turbo hose fitted, checked intercooler hose, ok

so once again i pull the pipes of the boost controlled solinoid, the lower one going to the actuator - i can suck on it and see the actuator move, and i can hold it fully open with my tongue in the pipe, so it can not be this section

the small hose from the metal pipe to the BCS, which i checked would hold vacumm last week, now will not !!! with a magnifying glass i can see what look like splits from someone using pliers to pull the pipe off

to be fair the pipe looks perished both ends, so i cut 20mm of each end, but have to warm the pipe in hot water to get it back on the metal pipe, i guess its flared one end.

drive car - huge boost everywhere, god dammit

i can remeber driving to liverpool 4 weeks ago, there was nothing wrong then, so in the space of two weeks ive lost low down boost and finally all boost just to a tiny split in this pipe

will order some 3mm silicone, or is it 5mm of ebay and replace the lot

thanks guys

If the restrictor plate is causing the light to come on its not allowing enough exhaust gases through to fool the sensors. You can increase the size of the hole in it to 8, 9, 10mm this will fine tune the plate to your car and allow just enough exaust crap through to prevent the light coming on.

Well done finding the fault.

Last edited by Shadeyman; 09-05-12 at 12:18.
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the small hose from the metal pipe to the BCS, which i checked would hold vacumm last week, now will not !!! with a magnifying glass i can see what look like splits from someone using pliers to pull the pipe off

to be fair the pipe looks perished both ends, so i cut 20mm of each end, but have to warm the pipe in hot water to get it back on the metal pipe, i guess its flared one end.

drive car - huge boost everywhere, god dammit

i can remeber driving to liverpool 4 weeks ago, there was nothing wrong then, so in the space of two weeks ive lost low down boost and finally all boost just to a tiny split in this pipe

will order some 3mm silicone, or is it 5mm of ebay and replace the lot

thanks guys
I did say! I used 3mm and 5mm Silicone, don't be tempted to use bigger tubing than the 3mm on the smaller pipes, I did and it leaked once it got hot. If necesarry use hot water it make it more flexible when fitting.
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I think everyone with a diesel should just replace the vacume hoses with silicone ones, they cost me only a few quid look nice and took a few mins to fit and I expect it to last years

P.s I used small clips to hold the big tube on the slightly smaller pipes
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anit that the truth, anybody that thinks wiesels are cheap to run needs a tap on the head, never had a car like this one - im a laughing stock in work - out there every week trying to fix it at lunch time
At the risk of rubbing salt into the wound...
 
(Post Link) post #21 of 23 Old 09-05-12 Thread Starter
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yes will be out with a drill tomorrow on the restrictor plate tomorrow cheers

5mm hose ordered but will add clips as necessary

thanks
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Just read this and glad you got it sorted
 
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Just found this thread. Assume same applies for GT ...Today I have the boost loss EGR has recently been replaced and I have cleaned MAP ..! think I need to identify these hoses so I can check them ...anyone got a pic or help me locate ....thanks
 
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