dropping acceleration while driving for no reason

This site contains affiliate links for which LandyZone may be compensated if you make a purchase.
As far as I'm aware the boost control sensor is the same as a map sensor.the sticky thread on this mentions the turbo boost control solenoid stc4198 but different all together
i asked him if it was maf sensor , he said no, its a boost control sensor ?, the dealership never hear of boost control sensor, so i'm abit confused ?
 
my td4 is 06 so the Pierburg 7.22684.09.0 be ok ?
NO

only use the proper bosch maf ..
see post number 56 ..
~~~~~~~~

what would give boost error in a Diagnostic Scanner
either the boost/m.a.p. sensor is faulty ..
and/or the connector to it has corroded ..
and/or there is a hole in the turbo / intercooler hose ..
and/or the turbo vacuum solenoid is not working properly ..

regarding your pic of that 'hole' ..
i don't know what i'm looking at .. i don't recognise the bits ..

but .. IF that pipe .. with the hole thats blowing oil out .. IS part of the turbo system ..
then that hole would be leaking pressure .. ..
 
NO

only use the proper bosch maf ..
see post number 56 ..
~~~~~~~~


either the boost/m.a.p. sensor is faulty ..
and/or the connector to it has corroded ..
and/or there is a hole in the turbo / intercooler hose ..
and/or the turbo vacuum solenoid is not working properly ..

regarding your pic of that 'hole' ..
i don't know what i'm looking at .. i don't recognise the bits ..

but .. IF that pipe .. with the hole thats blowing oil out .. IS part of the turbo system ..
then that hole would be leaking pressure .. ..
maybe this picture help better, the blue hose connected to egr on right going to black plastic where it closest to battery cable , i put a red circle around it and a red dot where hole is
 

Attachments

  • pcv-location (1).jpg
    pcv-location (1).jpg
    211.1 KB · Views: 791
2 different things MaF and maP sensors.ask him about MAP sensor I think this is what he's referring to

i ask him tomorrow , i asked him today was it a boost pressure sensor and he said no ?, he said boost control sensor ,, im thinking same thing myself ,, even the dealer never heard of boost control sensor,
think today he had a bad day, so i ask him again tomorrow
i also told him i was fitting the egr blank after i got this boost error problem fixed and he didn't like the idea of taking out egr and fitting the egr blank, but i do it afterwards
 
Last edited:
Looked in Haynes."the turbo boost pressure sensor is mounted on the right hand end of the intake manifold"it's the map sensor.the boost pressure control solenoid valve is located at the right hand rear corner of the engine cylinder block(underneath) the car needs jacked up so I think your looking at the map sensor just by another name
 
Looked in Haynes."the turbo boost pressure sensor is mounted on the right hand end of the intake manifold"it's the map sensor.the boost pressure control solenoid valve is located at the right hand rear corner of the engine cylinder block(underneath) the car needs jacked up so I think your looking at the map sensor just by another name
cheers for that, i put it to him tomorrow , think he had a bad day today
 
are the 2002 - 2004 boost pressure sensor same on 06 model ?

looks the same ..

here is one .. looking at the other side
BMW Land Rover MG ZT Rover 75 MAP (Boost) Sensor | World Car Parts > Store

might be worth taking the one you have .. out ..
give it a clean .. and clean the connector pins ..

that 'tube' has a diaphram inside ..
it could be that the 'tube' is full of oily gunk .. and not letting the diaphram work properly
( like what you would see in a dirty egr valve ..
( like what is leaking from that hose .. or pipe .. in the pic you posted

and he didn't like the idea of taking out egr
you need a different mechanic ;)

did he say Why he does not like the idea of blanking the egr ?

~~~~~~

in what part of europe are you ?

~~~~~
by the way .. my td4 is also an '06 ..
if need be .. i can take a pic of the m.a.p. sensor ..
 
looks the same ..

here is one .. looking at the other side
BMW Land Rover MG ZT Rover 75 MAP (Boost) Sensor | World Car Parts > Store

might be worth taking the one you have .. out ..
give it a clean .. and clean the connector pins ..

that 'tube' has a diaphram inside ..
it could be that the 'tube' is full of oily gunk .. and not letting the diaphram work properly
( like what you would see in a dirty egr valve ..
( like what is leaking from that hose .. or pipe .. in the pic you posted


you need a different mechanic ;)

did he say Why he does not like the idea of blanking the egr ?

~~~~~~

in what part of europe are you ?

~~~~~
by the way .. my td4 is also an '06 ..
if need be .. i can take a pic of the m.a.p. sensor ..

he didn't say why he didn't like, think he feels getting rid of egr is bad idea, but i do it myself, its only 10 min job,
i take off the map sensor myself and clean it, i had same problem with a jeep liberty, the map sensor needed cleaning
i'm in Ireland
i don't think he knows what the boost error from scan means ,
i clean the map , and if that doesnt work, i change it , then next thing maybe boost pressure solenoid
 
maybe this picture help better, the blue hose connected to egr on right going to black plastic where it closest to battery cable , i put a red circle around it and a red dot where hole is

ok .. now i see :)

a hole there will cause you to loose turbo pressure ..
that needs to be Fixed .

and whatever has caused that hole needs to be corrected ..
i.e. if it's a cable that's been rubbing against it .. move it away ..

that hole is Probably the main problem ..
 
Last edited:
ok .. now i see :)

a hole there will cause you to loose turbo pressure ..
that needs to be Fixed .

i'm getting a second hand one tomorrow from local dismantler, and i move the battery cable away from it so it doesnt happen again
funny thing is i didn't see a hole but there a lot of oil there and its worn good there , so must be leaking , he's idea is change that first and see if it helps, if not , change sensor, good job i ordered myself a Haynes manual lol
 
'iceman'

just to explain the EGR ..

the factory puts one in to decrease the amount of nitros-oxide in the exhaust emissions

in the uk .. for diesel engines .. only smoke particles are tested for in the MOT test
( nitros-oxide is not tested for )

what the EGR does .. is .. at certain engine rpm / load ..
some of the exhaust gases are fed back into the air-intake manifold ..
that's why EGR valves .. and the intake manifold get full of an oily gum like substance
and that .. reduces the efficiency of the engine ..
the EGR valve causes more problems than it solves ..

so fitting an egr delete/bypass will let the engine breathe air easier ..
result being .. less smoke particles in the exhaust .. better fuel mpg ..
smoother running .. slightly better acceleration ..
and no problems that are caused by a sticking egr valve :)
 
'iceman'

just to explain the EGR ..

the factory puts one in to decrease the amount of nitros-oxide in the exhaust emissions

in the uk .. for diesel engines .. only smoke particles are tested for in the MOT test
( nitros-oxide is not tested for )

what the EGR does .. is .. at certain engine rpm / load ..
some of the exhaust gases are fed back into the air-intake manifold ..
that's why EGR valves .. and the intake manifold get full of an oily gum like substance
and that .. reduces the efficiency of the engine ..
the EGR valve causes more problems than it solves ..

so fitting an egr delete/bypass will let the engine breathe air easier ..
result being .. less smoke particles in the exhaust .. better fuel mpg ..
smoother running .. slightly better acceleration ..
and no problems that are caused by a sticking egr valve :)
thanks for that
i have a egr blank . was just trying to sort out my loosing speed at 70 mph first before i installed it, i just asked my local grease monkey to see what he say about egr blanking but i read enough here and all over the web that tells me i get more plus's getting rid of egr ,
now if i can sort out my main problem with loss of speed at 70 mph, i be happy
 
funny thing is i didn't see a hole but there a lot of oil there and its worn good there

yeah .. it's an odd place to find a hole ..

( there's no cable near that .. on mine )

the oily stuff in the other pic .. suggests a leak for sure ..
like it's being blown out under pressure ..
looks similar to the mess one finds in an egr valve after a few years ..

btw: it's normal to find some oil in the turbo / intercooler hoses ..
 
yeah .. it's an odd place to find a hole ..

( there's no cable near that .. on mine )

the oily stuff in the other pic .. suggests a leak for sure ..
like it's being blown out under pressure ..
looks similar to the mess one finds in an egr valve after a few years ..

btw: it's normal to find some oil in the turbo / intercooler hoses ..

im picking up second hand one tomorrow and fit it and clean the map sensor and hope it fixes it
 
looks like i'm getting a Turbo Boost Control Solenoid(STC4198) , at stealership here, they want 210 euros and can get it from ebay delivered for 85 euros, so guess where i'm going, i hope this sorts it , as it seems a guessing game when fixing it
 
UPDATE FEB 7TH
i changed the Turbo Boost Control Solenoid(STC4198 and replaced the piece with the hole with used one from scrap yard
seems good so far at high speed on motorway over 75 mph

my guy suggested getting BMW SWIRL FLAPS BLANKING KIT to get rid of swirl flaps in the intake manifold

heres a link about it and how to do it
http://www.pmwltd.co.uk/swirl_flaps.pdf

has anyone here did it and where can you get the swirl flaps kits for td4
 
Back
Top