[presland123]

I had been getting the 17665 positive charge deviation error on VAGCOM on my wifes 04 beetle tdi thats done 76k. It only seems to do it once warm (after about 10-20 mins driving) and when accelerating up a hill, normally when in 5th up a hill.

Cleaned out the turbo vanes using one of the spray on (whilst on car) kits and alot of mess came out. Didnt fix the error code.

Tested the MAF on VAGCOM and it seems ok and the engine revs all the way to 5100 (which I am told it wouldnt with a duff MAF)

Changes some of the vac hoses, didnt fix the codes.

I noticed that when turning off the engine, the N75 valve was making 3-4 click type noises (I only noticed this recently), so thought it may be the valve so brought a new one, but no difference.

When under the car, the actuator seems to move by hand (although takes a lot of pressure). I have ordered a minivac so see if I can see if this is working and holding vacuum.

Any ideas? Is it normal for the N75 to click (its almost like a short sucking sound) when turning off the engine as I dont remember it doing this when we got the car a couple of years ago, but it was doing it before the problems started.

I'm trying to do as much as possible myself before taking to the dealers (as last time they were not much help). Or, anyone recommend anyone around Peterborough area.

Many thanks

 

[presland123]

update

thought i would disconnect the MAF plug and driven for about 75 miles and although it was slower accelerating i was able to cruise at 80 and when up hills no limp mode.

Does this mean that the MAF is on its way out afterall?

 

[chittychittybangbang]

Datalog the MAF requested vs. MAF actual value in engine measuring blocks before replacement. That is certainly a strange reaction by the MAF. Unplugging the MAF brings it to a default fallback value so you won't get limp, it'll just be slow as heck.

Older N75 valves clicked, the one on your car shouldn't. Test the vnt actuator with a mityvac, you're on the right track.

 

[presland123]

cheers Matey (oh and thanks for your help with my previous thread about removing the downpipe to clean the turbo vanes).

another strange thing since cleaning the vanes is that whilst i know its going iinto limp, its not showing the 17665 code anymore.

checked on VAGCOM before disconnecting and the MAF actual was, give or take, the same as the requested and when I gave it some revs they increased and stayed about the same. I assume that the MAF was ok, but them when disconnected and it didnt go into limp, made me doubt it - but like you say it was pretty slow getting to 80.

Do you think it could be starting to break down when it warms up. If i drove with VAGCOM on and the MAF connected, do you think that when it kicks into limp, I would then see the actual and requested for the MAF differ?

Another question, if its the actuator, can this be brought on its own as I can seem to find one available and can it be removed and replaced with the turbo on the car as if not, I reckon its going to have to be a dealer job and I guess they would want to replace the entire turbo!

Give me my 60's split bus any day, no complicate electrics/turbo to deal with!

 

[chittychittybangbang]

I would say the MAF is OK. Someone else had a low MAF reading that turned out to be a clogged exhaust. EGR can also do funny things. Maybe it;s another electrical problem like a short that is occurring when warm up. I would wait for the mityvac to test the vac line and actuator.

2004 actuator is hard to find but I think idparts.com or boraparts.com was able to find some. It has the smart sensor on it. should be able to remove on the car.

 

[presland123]

thats interesting, as the very first time that this fault showed itself was when the exhaust emission warning light showed on the dash, it went to the dealers who said that the only fault they found was a split turbo hose which they replaced.

Then, 10 miles later, the limp mode showed itself again, but no warning lights, but the dealers didnt want to know and couldnt recreate it as it only seems to happen at about 80 mph up a hill.

is there a sensor for the exhaust I can remove to see if thats creating limp mode?

As for the actuator, what's the smart sensor as my actuator seems to just a basic one, lever/rod on one side and the hoses pops on the pipe outlet the other end (although I can see that some have an connector plug mine doesn't)

 

[wren53]

I thought PD motors used the smart sensors? Doesn't it have a black cap on the actuator?

 

[presland123]

no, its just the actuator with the pipe out of the bottom - its an axr engine code - 1.9 tdi 06/03/04 if thats any help

oh, and im based in england if our models are different to the US ones

 

[chittychittybangbang]

OK, you don't have the smart sensor. You should be able to use the part numbers in te FAQ article.