Turbo problem no boost/underboost 04 Golf 1.9 BEW

Hi,

I have a 04 GOLF TDI with 96k miles. 2 weeks ago, I feel sudden power loss while cruising on a freeway. The engine seems impossible to go over 2200rpm on the top gear. And it stays like that even after reignition. Then the check engine light was on. I didn't see any smoke, the car is drivable, just less power. Much less. I had a previous turbo failure at 44k miles, which caused by a blown turbo emitting tons of smoke.

I drove it to Russlle VW in Cantonsville MD, they said it's turbo no boost or underboost. They suggest me to replace the turbo, which will cost almost $1600 in parts and $750 in labor. I think it's insane.

I have few questions for the experts in the forum:
1. Is this turbo completely dead? How do I find out easily?
2. What might be the cause?
3. I need to bring this car to other mechanics, is it safe to drive with the current underboost situations?

Much appreciated for your inputs!

Andy

Without the exact code, they could be giving you wrong information. It should be printed on the diagnosis report.

Anyway, a bunch of things could cause this failure. It's probably just a vacuum line that worked itself loose, or the N75 went bad.

Is it possible in limp mode? My car acted similarly as in limp mode, but reignite wouldn't restore the power.

I will try to look up the diagnoise to see if they have put the codes in?

jcrews said:

Without the exact code, they could be giving you wrong information. It should be printed on the diagnosis report.

Anyway, a bunch of things could cause this failure. It's probably just a vacuum line that worked itself loose, or the N75 went bad.

Click to expand...

With the colder weather, I've had the vacuum line for the turbo pinch itself off due to being less flexible. Rerouting the vacuum line to avoid this helped me out.

Not an expert but I had a very similar failure on a road trip. The loss of power was so sudden my wife thought we blew a tire as we were going up over a pass. It ended up being a gasket on the large air hose coming out of the intercooler (in front of front right wheel). It made a very distinct hissing sound as the rpms went up and the turbo pushed more air through the intercooler. It almost sounded like water hissing. I also had a loose connection on the air hose connected directly to the turbo with both these fixed I was getting better mileage and more power. They both must have gradually been going.

Not overly sure if these cars have the same trouble or not. But I had this problem several times on my 99.5 Jetta. Just driving down the road and the power would go away. Turned out to be the MAF. unplug it and see if the car runs better. They aren't near as prone to going bad but it can happen. It could also be an easy and much cheaper fix.

It is verly likely safe to drive - if you can keep from getting run over. It should not hurt the car.

Do not just let them dive in on the turbo. The problem is very likely much cheaper to repair.

So you can start with a VCDS checkout, by calling someone on the list that has a VCDS, or you can start with the physical stuff. You can check the codes and know where to start with a VCDS. The VCDS can also check to see if your turbo vanes are moving or not. Look at measuring block 43 field 2 before starting the engine - it should be about 0%, then start the car and it should be 100%. If it is not moving, then move on to the physical stuff.

Unplugging the MAF would give a pretty fair test of it, as mentioned above.

(You coudl start here if you wanted to.) The physical stuff would cost about $30 for a hand vacuum pump, like a MityVac. You hook this up to the vacuum line running down to your turbo vane operator - a vacuum operated diaphragm. When you pull a vacuum on it with the hand pump, it should move your turbo vane controller. But first just check that you can pull about 20" of mercury vacuum on it, and that it holds the vacuum.

If it does not hold the vacuum you have narrowed your failure mode to a bad vacuum line or a bad actuator diaphragm. You will have to get up on ramps or jackstands and pull the belly pan to figure out which is the problem.

If it does hold vacuum, then hook the vacuum pump up to the vacuum control solenoid - N75 relay- that controls the vacuum to the turbo vane controls. Start the car and watch the gauge on the vacuum pump. It should go to about 20" or more of vacuum.

If the vacuum is 20" or so, the N75 relay is not the problem. If the vacuum is near zero, it is probably a bad N75, since you have not reported any symptoms of a bad vacuum pump or loss of the vacuum system (poor brakes.)

Or you can locate a guru nearby and take it to him. Look in TDI 101 sticky threads for recommended mechanics.

Good luck,

Dan

jcrews said:

Without the exact code, they could be giving you wrong information. It should be printed on the diagnosis report.

Anyway, a bunch of things could cause this failure. It's probably just a vacuum line that worked itself loose, or the N75 went bad.

Click to expand...

He said it's '04 Golf with BEW engine. If I am not mistaken the vanes are actuated by a servo not vacuum line. In any case it sounds like that the ECU is cutting fuel delivery for whatever reason (faulty MAF, etc.)

The BEW turbine vane controls (I have one) has a vacuum operator on it, very similar to the ALH, except that it reports its position to the ECM. Troubleshooting and operation are very similar.

You are correct that it could be a reduced fueling situation.

I was providing turbo testing information, so he could see if it was bad before spending big bucks on a new one.

Dan

Check the EGR PIPES!!!!!!!!!!!!! These snap and it can be hard to see. Once the engine get warm and builds boost it opens(the accordian pipeis really thin) and gives you an underboost problem. Had about 10 cars(BEW) with this issue. Two block off plates and $30 later it can be fixed.

Pull the outlet hose off of the cold side of the turbo and check the impeller.

andy0310 said:

Is it possible in limp mode? My car acted similarly as in limp mode, but reignite wouldn't restore the power.

I will try to look up the diagnoise to see if they have put the codes in?

Click to expand...

it's limp mode alright , only permanent. Get the codes , without them you could end spending $$$ unecessarily

ive had a similar problem with mine i drove 800km to go see my trusted mechanic up north and it sucked going up hills (you had to think i was a compact gasser i was nailing the pedal and nothing, funny part was that i still got 47mpg lol going 90-100km/h) i dont remember what the code was but he had to replace a line and it worked like new so yea tell your mechanics to look at all the lines atached to the turbo.

WOW, I can't belive so many people here are helping me. I was thinking to get a Prius when the turbo went bad. Now forget about it. I am so confident that I can find help from TDI fans all over the world.

The diagnose gives:

P0118 Engine coolant temperature circuit high input
P0299 turbo/super charger underboost
P0673 cyclinder number 3 glow plug circuit

I will bring all the inputs to the dealership to see if they can find any leakage in the pipes.

Oliver, Great to see you here. Even the turbo still good, I'd like to get the Timing belt changed with your help. The car has 96k on it. TB will soon becomes problems. PM/email me your schedule.

Thanks.

Andy,
You would be much better off using one of these guys (listed below) or someone else in a nearby state from this list:
http://forums.tdiclub.com/showthread.php?t=130044

In all likelihood, seriously, really better off.

Maryland[FONT=&quot]

Mark I VWS
9633 Woodsboro Pike
Walkersville, MD 21793
(301) 845-4664
www.mark1vws.com
MAP

Oliver Wegener of 'RALLYVW' fame (Their crew chief)
Baltimore, MD
He is 'TDIRacing' here on the boards

Wheaton Service Center,
11308 Fern St
Silver Spring, MD 20902
(301) 949-3144
[/FONT][FONT=&quot]info@wheatonservicecenter.com [/FONT][FONT=&quot]
www.wheatonservicecenter.com
MAP

[/FONT]
[FONT=&quot]tmleadr03[/FONT]

I just realized which Oliver you were speaking to. Why not see if he will take it on?

Dan

Yes. I have contacted him. It will be hard for me to find a ride back home. So I will try to fit in his schedule so I can watch him trace down the problem and learn. (If he allows. LOL)

Thanks

I had the same problem with my 04. I changed my maf, brake light switch, and brake booster vacuum line without result. When I changed the vacuum line to the n75, the problem was fixed.

andy0310 said:

WOW, I can't belive so many people here are helping me. I was thinking to get a Prius when the turbo went bad. Now forget about it. I am so confident that I can find help from TDI fans all over the world.

The diagnose gives:

P0118 Engine coolant temperature circuit high input
P0299 turbo/super charger underboost
P0673 cyclinder number 3 glow plug circuit

I will bring all the inputs to the dealership to see if they can find any leakage in the pipes.

Oliver, Great to see you here. Even the turbo still good, I'd like to get the Timing belt changed with your help. The car has 96k on it. TB will soon becomes problems. PM/email me your schedule.

Thanks.

Click to expand...

check the hoses , if they are OK, check the turbo shaft for play, it sounds like the turbo is a goner, let's hope not

Also make sure the actuator isn't stuck. It should move 3/4" or so with a firm press on the arm with your thumb.