Golf 4: Location of the boost valve

Hi everyone!

I've been searching everywhere, but I can't find the turbocharger control valve on my PD engine. It's a Golf IV, manufactured in August 2001. Could you give me a tip about where it's located?

Best regards,
VipViper2000

Hi everyone!

I've been searching everywhere, but I can't find the boost pressure valve on my PD engine. It's a Golf IV, manufactured in August 2001. Could you give me a tip about where it's located?

Best regards,
VipViper2000

Hi,

What do you think the purpose of this 'boost control valve' is? Perhaps the hint will help us find an answer .

Greetings.

Eike.

My car is making a very strange hissing sound when I take my foot off the gas. I already posted about this further down. Since I think it might be the wastegate valve, I want to replace it. But I need to know where it's located.

Best regards,
VipViper2000

PD Motor = VTG turbocharger, therefore no wastegate. If it's whistling, there's a leak somewhere. Boost pressure is not being released!

Okay. Do I even have a boost valve? And where should I start looking to see if anything is leaking?

VipViper2000 wrote:

Aha. Do I even have a wastegate valve? And where should I start looking to see if anything is leaking?

Yes, you have a charge pressure control valve, but that only regulates the variable geometry turbocharger (VTG) and not the turbocharger pressure directly. Therefore, that part has nothing to do with the air noise.

What you've read there is the recirculation (or "popp off") valve in a gasoline engine. It makes a noise when releasing air. Diesel engines don't have anything like that!

The chattering sound of the VTG (Variable Train Gap) device is normal and can be heard clearly, with the volume varying depending on the previous load conditions.

The charge pressure control valve (for the VTG) should be easily locatable, even by someone with a prosthetic leg (see image).

Thank you for being so understanding and helping me.

Okay, the picture you took is great because I was working on that exact spot earlier. Mainly because, in addition to that strange noise, there's also a kind of clicking sound. I've now read that it's usually the AGR valve. But when I touch that (the silver, round thing), I don't feel anything. I don't think it's that, because if I press on the plastic part on the left, where the three valves you photographed are located, the clicking stops briefly and then starts again. Also, before my turbo was replaced, one of the two screws that hold the mounting bracket for the three valves was missing. I'm guessing that something might have been replaced there before.

So, what do you think the noise could be coming from? Because it's definitely not normal – first of all, he wasn't making that noise 3 months ago, and secondly, my father-in-law's car doesn't make the same noise either. I still have about 3 months of used car warranty, and by then, I want the car to be in a condition where major repairs are unlikely to be needed, you know what I mean.

Okay, let me just jot down everything that's been replaced so far, within the last approximately 6 months:

1. LMM
2. Battery.
3. Battery (yes, no typo. I've had a (new) dead battery several times. I'm curious to see if it's dead again when I return from vacation in 2 weeks...).
4. Complete PD (Professional Development) Units.
5. Engine control unit.
6. Turbo.

Okay, so those are the main things. Also, I had problems with the ESP at the beginning. I think Bertil knows exactly how I feel. I mean, I'm only 20 years old and I'm actually proud of my car, but it's already been in the workshop way more than 100 times compared to my old III.

Please help me. I want to go back to VW tomorrow and show them this.

Best regards,
VipViper2000

VipViper2000 wrote:

Okay, let me just jot down everything that's been replaced so far, within the last approximately 6 months: 1. LMM 2. Battery. 3. Battery (yes, no typo. I've had a (new) dead battery several times. I'm curious to see if it's dead again when I return from vacation in 2 weeks...). 4. Complete PD (Professional Development) Units. 5. Engine control unit. 6. Turbo.

Sooooo little...

4 PD elements, engine control unit, head gasket, VTG pressure system defective, oil cooler, water cooler, cooling fans (both), shock absorbers, tow hitch (3 times), mass airflow sensor replaced as a precaution, intercooler, and some other minor issues.

I wish you good luck with your search.
There's definitely a leak somewhere... Check the coolant level.


Edit:

I just remembered something about the battery. Is it also a lead-calcium battery, as required for a long-life VW? Otherwise, the battery might be constantly deeply discharged.

More information can also be found here: http://www.new.beetle24.de/kfzwissen/longlife/index.htm

LLK = Intercooler, right? Should they check the intercooler itself, or just the hoses?

Okay, about the battery - I have no idea, but surely they're going to install a proper battery there, right?? Well, you never know! So, you mean these noises can only be caused by some kind of leak, or something like that?

Best regards,
VipViper2000

VipViper2000 wrote:

LLK = Intercooler, right?

Yes!

Quote:

Should they check the tires, or the hoses?

Both!

Quote:

Okay, so about the battery - I have no idea, but I assume they'll install a proper battery there, right?? Well, you never know!

The problem is that many workshops still believe that all batteries are the same. Unfortunately, that's no longer the case.
If someone installs a standard battery in a Ford Mondeo that is designed for a LongLife battery, they will experience a problem. These cars use special batteries, and they are charged with 14.8V. This is too high a voltage for a standard lead-acid battery, and it can cause it to overheat or even explode.

Quote:

So, you're saying these noises can only be caused by some kind of leak, or what?

Okay, I think the noise is normal (as far as you're describing it). If it's a turbocharger noise, it could just be a leak.

Okay, thanks. I'm going to take it to the mechanic now. Let's see what he says about the clicking and the strange noise. I know which noise you mean when you let off the gas. It made that noise at the beginning when it was 'normal,' and I thought it was pretty cool. But now it sounds kind of 'broken.'

Well, let's see what happens.

Best regards,
VipViper2000

P.S.: Does anyone live in the Kassel area who has a diagnostic tool? I have the impression that they don't really know what they're doing at VW. They just plug in a diagnostic tool, and if it doesn't show anything, they're completely overwhelmed.