BMW M47N2 engine prob

[sprout99]

Hi

I have a 2005 BMW 120d M-Sport with a very annoying random prob.

When driving at a constant throttle and coming up against a hill or over take the car seems to hesitate for a split second then it's ok.

I'm losing the love for my car and have spent £350 so far on trying to solve it.

Has anyone got any good ideas on where to look next
I've eliminated....

MAF, MAP sensor, IAT sensor, EGR solenoid, Injector leak back.

All OK.

It's not putting fault light on dash and only fault code stored is 4B90 which relates to fuel pressure at start up.

HELP ME !!

thanks
Ian

 

[pgarner]

does the engine use a vnt turbo ?
might be the fins sticking, and hesitant while the boost picks up

might be a worth withwhile HDi picking up on this hes our derv expert

 

[sprout99]

it's booked into stealer tomorrow.

It has an electronic actuator which is a known problem on the VNT system. I have heard that when faulty it causes overboost and then momentary limp mode.

The problem has been finding the fault and then i have to convince the warranty company to cough up £1000 if thats it.


I'm begining to wish i'd kept my beloved denim blue 2003 8L A3 130pd known as 'old donkey'

 

[obi_waynne]

It does sound like a fuelling problem to me. Perhaps its just something simple like a bad contact on the pump or a slightly nackered pump. Does it do it with a full tank? I hope you get it sorted.

Should have kept the Audi! (Not that I'm biased or anything!)

 

[pgarner]

yeah the VAG diesels have the same issues the acunator sticks causing the blades to stick. with them its a case of take off the intake pipe and spray WD40 in and work by hand until its free.
dont know about the BMW setup tho

 

[sprout99]

I bit the bullet and put into Elvet BMW. No fault codes but on road test with Gt1 plugged in they noticed a problem with the EGR.

They tried to re-callibrate it but no luck.

I drove car home and it was still sh1t. I decided to unplug the EGR and test car.....no probs

Looks like spring in valve has given up and is allowing leakage. I cleaned it a while back and moving it then didn't take much effort but i didn't think
anything of it.

I'm going to run car over weekend with no EGR and see if it stays OK altough MIL light is on already !

 

[sprout99]

car has been adjusted again and is nearly rid of it's annoying hiccup

one more visit to doctor BMW and it should be ok again.

Next week i'll get my extra 40 ponies back....can't wait.

 

[obi_waynne]

Good luck with it and let us know how it feels with the extra 40 ponies. Glad you've managed to get to the bottom of it now.

 

[sprout99]

it was re-mapped until i had a DDE update which wiped it - GRRR!!!

was very quick - a pleasure to drive

 

[obi_waynne]

Ooh! Bad luck. Will you get a disocounted 2nd remap? It's a shame you can't back up the maps.

 

[sprout99]

offer of a few beers should get me it back.

 

[obi_waynne]

Thats a sound plan. Get him drunk then nick the laptop for an hour!

 

[sprout99]

e's based in chesterfield so i'm sending ECU to him with a cheque for somes beers

 

[sprout99]

car is now brainless and waiting for genetic modification results
back on road wednesday - i hope

 

[obi_waynne]

We normally get brainless drivers down our way - rather than brainless cars.

 

[sprout99]

car might get it's brain back but i doubt i will

 

[obi_waynne]

At least you'll be able to claim insanity when you get stopped!

 

[sprout99]

for driving like a looney .......?

:embarrest:

 

[obi_waynne]

 

[sprout99]

finally got back to former glory - wow it's fast !!

just need to get wheels re-furbed after crimbo and all will be perfect

 

[obi_waynne]

Cool. That was reasonably quick then. I bet you are dead chuffed with that!

 

[sprout99]

i've got that new car syndrome where i just want to go out and drive

:love:

 

[obi_waynne]

I know it well. Your wallet will cure you of that addiction though!

 

[sprout99]

it does about 43mpg with some varied driving

My old A3 (bless her!) did 49+

 

[obi_waynne]

Thats still pretty good. Damn I hate you now!

 

[Maxy]

It features an electric actuator that is a known problem in the system of WND. I heard that when defective, causes momentary over boost and smoothly.

 

[Prince]

Shall we assume that yours has stopped working?