Under boost problem p0299, is this the resolution?

[Simo]

Hi Everyone. This is my first post, but I've been a member for about a year. Great forum, it's nice to see everyone loves the new Scirocco as much as me!

I've had a search for the p0299 on forum but nothing really came so I decided to create a new thread if that's ok? If you could it moved to some where appropriate.

I'm pretty sure I've answered my own question but it would me be great if you guys could just confirm it. I have a Candy white Scirocco GT TDI 140 58 plate pre facelift and have had for just over 2 years

I've had the dreaded P0299 under boost fault come up. I have no boost until about 2.5k rpm then it comes in with a vengeance. So far I have visually checked the vacuum hose and replaced the N75 to no avail. So I decided to suck on the hose that leads into the turbo actuator and couldn't create a vacuum. Just make sure I full removed the hose and did the same to that and the hose is ok.

Does this mean the diaphragm on the actuator has gone? Or have I tested the actuator wrong? It was in situ when I tested, were the conditions wrong.... I.e did I have to remove anything else?

Just to add, I've plugged the car in and used the rev app on android and had live telemetry when I drove it reproduce the fault. Before the fault came up, it's was only producing half the pressure from the turbo (I can't recall the figure but it was something like .5 bar?).

So anyways, is this a simple case of replacing my actuator?

Thank you in advance for your replies if i forget them. I look forward to hearing from you all. Sorry for the long post too

James

[bames]

Hi Simo,

I've had exactly the same issue recently, with under boost and coil light coming on. (Driving a 59 Scirocco 2.0TID 140)
Mine was in the garage and the mechanics changed a sensor (I forget which) and cleaned EGR and throttle body.
Issue is still there.

I receive; "00665 Boost Pressure Regulation Control Range Not Reached - PO299"
Next step is testing the actuator - the garage suggested that and plenty of forums have as well.

Although it is a 2.5l TDI - one guy had the exact fault:

"VAG 16683 (P0299) 000665 - Boost Pressure Regulation: Control Range Not Reached

Possible Symptoms

Reduced Power Output
Limp Mode

Possible Causes

Hoses/Pipes incorrect connected, disconnected or leaking
Charger Pressure Control defective
Turbocharger faulty
Diverter Valve faulty

Possible Solutions

Check Hoses/Pipes to/between Components
Check / Clean / Replace Charge Pressure Control
Check Turbocharger
Check Diverter Valve"

taken from site <http://www.volkswagenforum.co.uk/f118/low-boost-pressure-problem-4050.html>

[Simo]

Hi Bames,

Sorry to hear the work so far hasn't cured the problem. I'm not the best clued up on turbo systems so I've just researched and researched, friends and family are getting annoyed with it now haha!

I'm going to take the plunge this week and replace it. From what I've read the actuator should hold a vacuum. I've read also that if the actuator doesn't move then replace, if it either one or the other or both then replace.

I'll put a few links on here from other forums if that isn't against the rules of the forum. Hopefully these will help.

Troubleshoot limp mode http://forums.tdiclub.com/showthread.php?t=179589

http://uk-mkivs.net/topic/34834-vnt-tdi ... -problems/

How a turbo works http://youtu.be/vGhlgphrBxA

Video of a bloke changing his actuator on an Audi looks like the same engine as mine
http://youtu.be/1CztBcMtlrw

Hope this helps

I'll post an update on here once it's done. Fingers crossed. As much as I love my motorbike, I'm not enjoying this weather to and from work haha!

[shshivji]

You could do with a garage that knows these cars well to diagnose the issue pal, where abouts are you??

Shak

[bames]

Hi Shak - I am based in Gloucester myself and have thought about taking it to a VW specialist.

Simo - any luck with replacing the actuator?

[Simo]

Hi Guys. Have been busy lately so forgot to reply. It's been done, it's not a bad job. I can't stress enough how important it is to use a 1/4" drive ratchet set though with a deep socket. That is a must! Expect a few cuts from the exhaust manifold hear shield also haha.
I was in a hurry and didn't have time to let the lock tight dry and knocked the top locking nut when putting it in so had to judge how much I knocked it and put it back to how it was. It's been driving fine for about a month, I decided to take it up to 100mph (private road of course) and it went into limp mode with Over boost. So I'm going to take it off again soon and readjust it as I've still got my old one to measure it off, which by the way was knackered (failing to hold vacuum).

So key points:

•Patience
•1/4" ratchet set with a deep socket (May have to trim it down if it's too deep)
• Let the lock tight dry, which you get with the kit, dry (both locking nuts).

Hope this helps

Also, got my actuator from Darkside Developments. Just email them the part number, which you'll find on the actuator. Quick delivery, happy days.