2000 Sport TDI - Limp Mode / Over Boost

ruffrida

ruffrida

Registered User
Joined
Feb 20, 2012
Messages
1,934
Reaction score
317
Points
83
Location
Pie eating land
Hi Ya'll,

Now ihave a new problem, but it is an over boost issue so not that much of an issue, MAf? Egr? or N75?

Basically the car revs fine untilll you put it under extreme load, ie, high revs going up an hill, car backs off like it has lost boost or turbo, very random !!

I have taken it for a good run today and i am convinced it also juddrs slightly when going up a gradual hill in limp mode.

Happy to hear all sugestions, feel free,

Thanks
 
hey

if it your usual high milage car then you it will 9 times out of ten be the varibale vanes sticking in the turbo. you could run a innotec turbo cleaner kit through it which is reasonably cheap round 70-100 quid job done. only prob is this doesnt always cure the probelm, so you could either replace the turbo unit or get the turbo reconditiond. if this is the problem then when sorted you will see a vast improvment in drivability of the car and no more lip home mode. usual fault codes thrown up will be "charge pressure control" negative deviaiton. get it on the vag com first tho before jumping to conclusion as this could prove very cost effective.

james
 
Hey james,

Never even thought of that, after reading all the faults on here for N75 failure i just presummed it was that or the Maf, i have ordered both anyway just in case.
I will have a look for these turbo cleaners, its totalally new to me.

Cheers for the advise, will keep you posted.
 
Or maybe you could try this http://www.audi-sport.net/vb/a4-s4-forum-b5-chassis/107121-un-sticking-your-tdi-vnt-turbo-vanes.html but note the post's made the guy called Turbo Unit ,,,, he might be right he might be not, i don't know .... i'm guessing he's in the trade of supplying replacement turbo's or refurbishing them so he might not want people to know about a quick and easy fix or he may indeed be telling the truth... read the thread and make your own mind up but it's seems to have worked for plenty of people
 
That sounds like a plan, will be sending the misses out to get me some MR Muscle oven cleaner,

Cheers Markyboy
 
yep thats the stuff but have also heard of the mr muscle being used before. i tried the innotec kit on my 130 TDI but it only made a slight difference and would still go into limp mode when under extreme loads. the turbo can be removed and stripped and cleaned which will work 100% but for the labour charge incurred then i decided to buy a new turbo for £562 genuine unit. this worked an absolute treat and is a different car now.

james
 
Hi James,

I think i wil lbe trying cleaning the turbo and replacing the maf & N75 before i go spending that kind of money, cheers fo rthe advice though.

I have noticed this morning that it has now started to it at a lot lower revs, 5th gear about 2200revs it did it this morning.
 
hey

An easy way to check the vanes which if you have any form of mechanical knowledge is easy, would be to remove the actuator rod that connects the the vanes shaft. theres a little circlip on there they is easy to remove and remove the actuator arm from the vanes shaft. now try and move the vane shaft with you fingers, this should be easily done if it is hard to move and feels very stiff then this is defo the issue, as you should be able to flick it with you nail open, closed, open, closed, but if gunged up with soot then it will prevent it from moving easily hence casuing over boost and limp mode.

james
 
yep thats exactly it but obviously there is alot involved and if this isnt the issue then it would be abit annoying to do all that to find it not that. so best thing to do would to try and move then before unbolting the turbo by removing the actuator rod.

james
 
Yeh someone else said that last night, so i will be removing the actuator rod first then going from there, my new Maf has arrived today aswel just need to pick it up from post office,
Cheers
 
Fitted the new Maf last night, great response when turbo kicks in round town, but as soon as you get in the high gears it goes into limp mode/ over boost again !
Roll on saturday when i have the time to check the actuater, egr & turbo vaines
 
Recieved my new Maf, & N75 at the weekend !

Tried both and it has made very little diffrence, whilst i had some time on me hands i also removed the throttle body which was full of s***e, cleaned it all back to shiney, but this has made no diffrence at all.

My friend mensioned it could be the Actuator sticking, i have checked this but it only seems to move a very slight bit, and i mean not even a cm, is this right??
 
could you move it easily, by easily i mean flick it from side to side or did u have to give it some effort? it should move really easily. mine was very notchy which i why i changed it and it done the trick. you could feel that it was all gunked up with soot.

james
 
BuckleyTDI said:
could you move it easily, by easily i mean flick it from side to side or did u have to give it some effort? it should move really easily. mine was very notchy which i why i changed it and it done the trick. you could feel that it was all gunked up with soot.

james
Click to expand...

Hi James, no it would move a few mm, pushing down on the rod from above, it now aswel if you sit and rev it hard it makes a loud wastegate noise and cuts out compeltly
 
  • Like
Reactions: SPORT BACK SI
audi upgrades
Defo not moving that far marky, i have only tried from above with the rod still connected as i could not remove it due to space and time, i have also been told, due to my engine been the AHF and not a PD it does not have a variable vain turbo, is this right??
 
hello mate

your engine does still run a VNT turbo the same as the PD,s, what you need to make sure is that you completely dissconnet the actuator arm from the vane shaft, and move it out the way just enough for you to be able to freely move the vane shaft backwards and forwards. it wont move with the actuator still attached. if you still have no movemen then, this will mean u vanes need a clean or new turbo time. where abouts are you as i dont mind having a look if your not to far?

james

james
 
BuckleyTDI said:
hello mate

your engine does still run a VNT turbo the same as the PD,s, what you need to make sure is that you completely dissconnet the actuator arm from the vane shaft, and move it out the way just enough for you to be able to freely move the vane shaft backwards and forwards. it wont move with the actuator still attached. if you still have no movemen then, this will mean u vanes need a clean or new turbo time. where abouts are you as i dont mind having a look if your not to far?

james

james
Click to expand...

Hi Bud,

Im in wigan not sure where you are.

Defo seems like i need to disconnect it and try it again
 
Oh that's bit of a trek, soz dude. Yer defo worth disconnecting if you have the time, it's the only way u can be sure it's that.
Janes
 
BuckleyTDI said:
Oh that's bit of a trek, soz dude. Yer defo worth disconnecting if you have the time, it's the only way u can be sure it's that.
Janes
Click to expand...

Going to have a look at it again at the weekend as i come to work its dark, i go home its dark.

I have noticed this morning that on start up in a morning it really struggles then once it starts its throwing loads of smoke out.
 
Hi Marky

when the VNT is actually assembled the rod moves approx 10-12 mm for a full sweep of the Vanes
on all the GT1749V, VA & VB's i have here ;) (thats how far it moves here and the VB is brand new in Audi Wrapper (ie:not sooted up)
that one has the ring & VNT removed so moves as far as the actuator will go.

I only have these 3 to measure so other units may vary ;)
 
Cheers Cobra,
I have re checked it again and it moves about 5mm tops when conected.
Thanks for the advise fella's only 2 more days till the weekend then can have another look, still got me can of mr muscle so hopefully ge ton that
 
Hi,
Welli have had the actuator off today and it moves fine !

So onto the Vain clean, did as discribed, left for 2 hrs still no different.

How far is the arm meant to move once the actuator is removed? As i did notice when i was re fitting the actuator the arm woruld only move a slight bit (couple of mm each way) and when i was trying to get the bolts back on i had to compress the actuator quite alot to get it tight, is this right?
 
do you mean the actuator moves fine, or the shaft it attaches to moves fine? the shaft it attachs to should move about 10mm from one side to the other with no resistence

james
 
BuckleyTDI said:
do you mean the actuator moves fine, or the shaft it attaches to moves fine? the shaft it attachs to should move about 10mm from one side to the other with no resistence

james
Click to expand...

Yeh the actuator moves fine, but like i said on re fitting i have to compress the actuator quite alot to get the nuts back on, the arm only moves about 2mm either way
 
well that isnt how is should move defo around 10mm movement so if it not closing of enough you will go into overboost limpm mode

james
 
Took it bit for the third time yesterday and the wastegate arm is sticking.

Once the actuator is removed the arm is stuck in the down position and wont budge, until you prize it up with a screwdriver.
When the arm is at the top thier is plenty of movement and you dont have to compress the actuator to re-fit. I sepent a good half hr just pusing it up and down trying to free it off as much as possible. It seems to be a lot freeier but still goes into limp mode.
I have also done the mr muscle trick again which has seemed to make a diffrence as the limp mode does not kick in till their is a lot of strain / pressure.
 
thats the baby, i used the innotec kit which did make a difference, i seemed to go into limp alot later then before, but still did. only other choose it to take it of and strip it or new turbo time.

james
 
Just for info,,, today i cleaned the inlet manifold out and also the EGR valve.... both of which were really full of crudd .... whilst i had it all apart i fitted a clean peice of silicone pipe to the actuator on the turbo to check the movement of the vanes and just by sucking on the pipe i was able to feel the actuator arm move a good 20mm ( no jokes about sucking please ) :) .... anyway my point is there's no need for a vac pump or anything to check it's all free ... my car was fine before the clean of the EGR so i'm guessing if you can't make the actuator move it's full movement by sucking on it yourself then there is a problem .... also RE: the EGR rather than block it off all i've done is remove the VAC hose that operates it and blanked it off with an old bolt or as some have mentioned a golf tee... so far no engine lights and the valve no longer opperates as it's in a closed state normally....... tickover on the car is a little smoother after cleaning everything but driving it just seems the same ... MPG may improve, i've got to do a few work runs before i'll know that but i'm glad it's no longer chucking all that crap in the inlet after what i cleaned out today
 
Thanks for the link to the Videos Nick i hadn't seen those before.... would you recommend a strip down and clean on a car with 130,000 even though it wasn't showing any problems ??? i prefer prevention rather than cure :) also Top work on Prawns car i've been following his thread very closely from the start as i own a 1.8t A3 also ..... well the wife does... even if it was mine :)
 
I fitted a new vacum pipe to the actuator at the weekend as mine was that perished if you sucked onit (alot of sucking going on ere, lol) the pipe would close as it was that soft.
back ion the day i had a Mg zs tdi, on which i blanked off the Egr which made quite alot of diffrence to its top end power, how much diffreence does it make with the Audi Tdi's??
 
You must log in or register to reply here.

Similar threads

a3tdi2001
110 TDI Boost / Limp Mode
Replies
1
Views
869
finesse
finesse
D
Limp Mode/Boost problem please help
Replies
7
Views
1K
djjay
D
A
Limp Mode - TDI - 17965 P1557
Replies
3
Views
9K
Essflee
E
jay22s3
limp mode
Replies
5
Views
854
jay22s3
jay22s3
A
limp mode?
Replies
13
Views
1K
finesse
finesse
Top
Back