19TDI 110 1997 power loss !!!!!!!!!!

[nobbie1010]

Hi There. Please can someone help, I used to have a full head of hair but now I have a bald spot :aargh4:
I have a 1997 (P) A4 110 bhp (red i) avant with 218000 miles on the clock (about the same as the space shuttle). I have owned it for 5 years and has never ever missed a beat until now. It all started a couple of months ago on the motorway when all of a sudden the car seem to loose turbo boost. I turned it off and on again and all seemed ok again. It did'nt do it again for a couple of weeks then it started again and has now started to do it more and more often (every time out) I have taken the actuator off and checked it with a mityvac. I have checked the lever that the actuator goes on to and that seems ok ish, I seems to have a bit of a lip on it but is nice and free.
I did find that the top turbo hose had a hole in it and now has a samco hose fitted (racer !) I have also changed some of the small vacuum hoses because they were suspect. I have read somewhere that you can do away with the boost control valve that the actuator pipe goes onto and put the hose straight onto some other hose but I dont know where to put it to.
I have not had it put on a fault code reader as yet. I have not as yet tried to swap over the egr control valve with the turbo boost valve. If I do that can I just swap the pipe over or do I have to swap them over pipe for pipe and electricaly. I do seam to have a small about of soot coming from the flexy joint on the exhaust but I dont think that as anything to do with it. I have noticed a small amont if oil in the intercooler hoses, Is this normal ?
Please, please help its started to get to me now :biglaugh:

[Muddy19]

my suspect - maf. common problem which results in powerloss and the famous (switch off/switch o symptoms). feels like you hit a wall of air, and the engine doesnt rev as quickly and feels sluggish. (like drivin a transit). you will feel this a lot more uphills.

my advice, - get it code read. - it will tell you if your maf, and or egr are playing up.

sorry cudn't be of more help

[nobbie1010]

Cheers.
I will try and get it code read today. I will let you know how I get on.

Thanks again :Blush:

[fantasiagreen]

Agree with the above - try to get the fault codes read. Having the same problem with mine although very rarely - my actuator didn't move as much as it should with a vacuum applied so I suspect the variable vanes in my turbo need cleaning.

From what I've read on here a small amount of oil in the intercooler pipework is entirely normal.

[pauloliver]

i have been told maf failures cant be read on vag com? anyway it sounds like a duff maf to me, i had the same troubles on my 110 tdi seat toledo. Try disconnecting it and seeing if it makes any difference, on mine its performance went close to normal but it ran really roughly, few days later a new maf arrived and i was a very happy boy indeed

[Minimango]

Ok i just had a problem similar to this. symptoms include:
-rapid warm up
-sudden powerloss after 20 mins of driving, not shutdown but it became slow to pull off
-slight shuddering throughout the car
-vag says that the engine is running too fast in idle.

i changed my fuel,air and oil filter, spark plugs and cables and put a bottle of injector cleaner into the fuel. cleaned the MAF. Still nothing
It was the REV SENSOR. I went to a garage which specialises in german cars and he said it was quite common in Audi's. Luckily it is a cheap replacement.
Hope this is of help to others with the same problem.

[richard3009]

I had exactly the same issue, mine was seriously down on power very smokey, and stopping and restarting the engine would resolve it for a few miles.

Turned out to be a split in the intercooler hose that runs above the fuel filter.

[Minimango]

I also got the feeling that the engine was running faster than what the odo was reading.
As it was a rev sensor problem, it could be that it the sensor was only reading only half of what the engine was doing.
At least one good thing came from it, i did all the fluid and filter changes that you would expect from a good service trying to find the problem. The car is running nicel and clean now.

[nobbie1010]

Cheers guys
Sorry I have been working away so have not had internet.
I have just done 400+ miles in the car !
It runs as normal when driving normaly along the b roads for as long as I want but as soon as I got onto the motorway and put my boot down a bit it just went into limp mode (for the next 185 miles however) still did about 80 (irm sorry 70 mph) !! but when I went up the hills it dropped down.
I have just spoken to the motorfactors and they want £115 + vat for a maf so I will have a look arround.

I will keep you informed.
Any more ideas please !!

regards and thanks

[Muddy19]

yup that's the sh*t.

new maf is cheaper from the ********. (audi dealer to you and me). thats the only place i wud recomennd gettin one from. i have heard that a replacement pierburg one from euro car parts is supposed to be better but i have not heard enuf positive stuff to recommend this.

i sprayed//soaked my maf and placed it in a freezer bag (zip bag). then i placed masking tape on the edges to leave a square in the middle. this was to allow the air only to go through the middle and therefore more air on the sensor. (or all the air on the sensor). after bout 500miles i took the tape off.

tip - try driving wit a lighter foot on moterway. just tip the gas pedal. for me, i have boost longer like this and speed wise its better. but you will pick up a bit slower, but it shud still go to 110mph+. (sorry, i meant k/ph)

[4udi]

hi can you tell where the rev sensor is as when the engine is idle and i put my foot down on the pedal revs go upto around 4000 revs and then drop back down to 2400 revs even though i stil have my foot pushed down all the way also im getting power loss continuosly

[nobbie1010]

Yeh
I put a new MAF from German Swedish and there is still no difference.
The code reader said something about boost presures not in tolerance or something.

Still pulling my hair out although I have put another few thousand miles on her since & now I have another problem.
At about 75mph the abs light comes on with the brake warning light.
I think it might be time to pension her off. Also the wife hit a bollard in ASDA car park yesterday and now I need a front left indicator lamp and bumper paint.

When will it all end :aargh4:

Boo Hoo

[4udi]

i hav done 15,000 miles with this problem :zx11:

[richard3009]

mine has been like it for 1000 miles now, im damned if i can get to the bottom of it, bring back carbs and points

[andysuth]

Mine exhibited a real drop in MPG and quite a bad acceleration after 60mph.

I asked a couple of diesel experts if they'd have a look and whilst under the bonnet I spotted one of the hoses had a split in it.

I've patched that with heat shrink and vasaline and it's ok right now, MPG back, Acceleration back, have you had a look for split hoses?

-AS

[nobbie1010]

I have replaced one but I need to go through the rest.
Sometimes I get a high pitched noise just before the power loss.
However it is great for fuel econamy :D

[dub love]

could be egr valve clogged in carbon. huge thread on this i posted.. new map sensor,?

[richard3009]

mine is intermittent sometimes i get full power, but christ when it smokes its serious

[dub love]

i could put money on it that the egr valve is clogged up with carbon.. take it off i used cillit bang and tooth brush to clean mine up, took a while, also have to change the map sensor as all the carbon will have clogged that also. i have big thread on this in B6 section.. let me no if you need any more help.

[richard3009]

thanks i will check that out, its as though the engine chokes and then clears itself especially at high torque

[richard3009]

Are there and phtos of the egr valve and removal clean and replace procedure anywhere, and maf cleaning if required

cheers

[nobbie1010]

Mine when it loses power there is no smoke its just down on power !

[andysuth]

High pitched noise before the power loss is probably the turbo kicking in.

That would probably point to the vacuum tubes being ok.

-AS

[nobbie1010]

OK Its been a long time. However I still have the problem with my car but until now have been working flat out and had no time to sort.

I now hav the VAG COM diagnostic stuff on my laptop. It works really well.
If anyone wants one I have the contact details of a great guy who sells them.

Anyway. The fault code has come up as the following:

00575 intake manifold pressure
17-10 control difference - intermittent

Can anyone pin point me as to where I can fix the problem ?

Cheers...........:1zhelp:

[ini]

I would suspect a vacuum leak in the control system, or sticking VNT mechanism. (probably turbo vnt)

Without any mechanical work, the best way to sort it is: load up the car and go for a very long drive for at least a few hours. (the idea is to make the turbo/exhaust system very hot for an extended period, which can burn/work off any offending crud.

If you can not load the car (pulling a trailer or filling it with heavy mates) drive at relatively high rpm's, or in a very hilly area.

[nobbie1010]

Cheers.
Are you saying I might need a new Turbo ?
The problem started off only now and then. Now its more now !

[ini]

A sticking VNT mechanism (internal turbo wastegate) is just a build up of soot/crud affecting the moving vanes & actuator ring inside the turbo. It only needs to very slightly restrict the free movement to cause underboost/overboost.

Essentially the turbo is just a bit dirty and needs to be cleaned via either heavy usage/temperatures, chemically cleaning with the turbo still on the car, or by removing and scraping off the crud manually.

The dealer will always replace the full turbo unit if this is the problem, as they class it as 'non-repairable'.

90% of the time the turbo is perfectly fine, as it was designed to last the lifetime of the car.