[02smoker]

HELP PLEASE! Newbie here, Hey all, I have a 2002 VW jetta TDI and I think my VNT actuator is stuck. Have gotten a P1556 code, Charge Pressure Negative Deviation. Going to check the N75 valve today and see it it is working correctly. All the vacuum lines appear to be ok with no holes. I tried to move the VNT actuator by hand while its still attached to the turbo in my car and can only get it to move a tinny bit and it was pretty hard to push! Any info would be great. Is it suppose to push that hard? And if it is a bad actuator how do I remove it while leaving the turbo in the car?
Thanks all.

 

[Seatman]

Hi there, welcometomyturbodies.
Check through the faq, you'll probably find the answer there.

http://www.myturbodiesel.com/1000q/multi/limp-mode-TDI-fix.htm

 

[chittychittybangbang]

It might not be the actuator. Disconnect the rod and move the lever to isolate the sticking to the actuator or the VNT vanes inside the turbo. http://www.myturbodiesel.com/1000q/a4/VNT-wastegate-adjust.htm Read this article for more testing. If it's the VNT vanes you can probably clean them. If it's the actuator, replace the actuator.

 

[02smoker]

Thanks guys, I checked out the links and it was helpful. After I looked at the links I rented a vacuum tester, and hooked it up to the actuator and the actuator didnt hold any vacuum. Got it to go to about 18 inch pounds and it leaked out pretty quick. So I'm thinking thats the problem. Plan on replacing that this weekend. Would a bad actuator cause that error code of P1556 Charge Pressure Negative Deviation? It seems to me that if its not holding any vacuum, then the wastegate part is just staying open and not allowing it to boost enough at a higher speed. What do you guys think?
Thanks

 

[Seatman]

It's different with the vnt turbo, it actually uses the vacuum to increase the boost unlike mine which has a waste gate. Yours is a vnt, have a look at these videos on how it operates? There's quite a few on youtube.

http://www.youtube.com/watch?v=Gc2awh0O0Bc

http://www.youtube.com/watch?v=KgVrpiFfp8U&feature=related

I'm going to look up info on how the wastegate turbo works.

 

[Seatman]

So the wastegate turbo operates by diverting the gases via the wastegate to prevent the turbo overboosting. Interesting stuff this.

http://www.ehow.com/how-does_5412665_turbo-wastegate-works.html

 

[yvon g]

i also put a hand held vacuum pump to my bad vnt actuator. never moved one bit. i replaced actuator because by putting pump directly to actuator, your eliminating bad hoses, n75, etc. took about 1 1/2 hours to replaced. the circlip on turbo lever is hard to take off and even trickier to put on. i used a magnet to hold the clip and push it in the groove on turbo lever. good luck.

 

[02smoker]

Thanks Seatman for the vidoe's, they were pretty helpful. And Yvon g, did you have to use the 10mm socket or wrench to take the nut off? Yeah that clip looks pretty tricky to take off and put on again.

 

[02smoker]

Hey Yvon g, I'm looking at the pics of the actuator on here and the one that I bought is complete and has the rod and clip, ect.. everything I need. So my question is, do I only need to take the clip off and the nut that is attached to the side of the turbo? From the pics here it looks like the 10mm nut on the top side of the actuator dosen't need to come off, just the one above it and to the left. Is this correct?
Thanks

 

[chittychittybangbang]

Did you read the article that shows step by step instructions on how to remove it? http://www.myturbodiesel.com/1000q/a4/VNT-wastegate-adjust.htm There are 2x 10mm nuts and the clip.

 

[02smoker]

Yes I did, it showed the 10mm nut with the wrench on it and it said x2. It also talked about the 10mm nut on the actuator rod. So I wasn't sure if that was the 2 10mm nuts that the reading was talking about or if the 2nd 10mm nut was the one just to the left of the actuator rod on the turbo that has the arrow that goes thought it saying acuator rod. In that pic it looks like there is a nut just inside that arrow on the turbo. Is that a nut that I can remove along with the clip to take the actuator off? And the actuator I will be getting is a complete unit compared to ones that do not have the actuator rode assembled already.

 

[02smoker]

So I guess I was just wondering if that nut that I was talking about, or it looks like a nut that is on the side of the turbo just left of the actuator rod, is that the only nut I would need to take off along with the clip to remove the whole actuator?

 

[bwolfgti]

So I guess I was just wondering if that nut that I was talking about, or it looks like a nut that is on the side of the turbo just left of the actuator rod, is that the only nut I would need to take off along with the clip to remove the whole actuator?

Just replaced this on my friends car today. Just take the two 10mm nuts off that hold the actuator to the bracket remove the clip and it comes right out. The clip is a pain to get off, i used a big pick and penetrating oil to get it off but it still took some work. Should only be about a 20 minute job if everything goes smoothly.

 

[02smoker]

Well that is a good news to hear! So those 2 10mm nuts, are they both on the actuator itself? Dont mean to sound dumb, but I haven't got under the hood all the way to see it very clear. The one on the top side of the actuator and the other one is where?

 

[02smoker]

Also did you do this job from above or below the car?

 

[02smoker]

Never mind guys, Im an idiot. I looked at the pic closer and I see the other 10mm nut behing the rod on the other side. Thanks for everyones help!:thumbsup This is the most helpful site I have seen and glad I joined!
I am gonna try to get that actuator off this weekend and get it back on the road. Do have one more question. How reliable are these turbo's? I haven't noticed any outstanding oil in my intercooler tube, but I can get a seal kit for the turbo for a great price. What do you guys think? Turbo's seem to hold up on these TDI's? I have 140,000 miles on my TDI and only second major problem really.

 

[chittychittybangbang]

Seal kit for the turbo for a great price....is it from e m ia t a, p r o t he in SC? If so, I personally would not buy any of his parts after a very bad experience and IMHO, most if not all of his parts are low quality copycat parts.

 

[02smoker]

actually yes. well crap, I guess I will count that out then. I think I might be able to find another one somewhere then, maybe a few more dollars, but if you say its a bad idea from the place I think your saying, then I wont get it, unfortunately that is where I got the actuator from. do you think that will hold up for me? I needed one bad so I could get back to my family this weekend.

 

[02smoker]

also, is that a good idea to put a seal kit in the turbo? Any major problems with these turbo's? Or do they tend to hold up pretty good?
Thanks

 

[Seatman]

Don't mess with the turbo if it isn't broke because you'll break it lol. They last a hell of a long time as long as you look after oil changes etc. If it does go though give it to a specialist to repair. They balance them to spin at like 200,000 rpm or something mental.