04 BEW loss of power; shaking when accelerating.

Ryanr912

Member
Joined
Mar 25, 2008
Location
Brooklyn, CT
TDI
2004 Jetta PD
Driving into work today my car started driving horribly. At highway speed it just lost power and started decelerating with the pedal to the floor. Going up hills I was only able to drive ~55 mph (until I hit the next downslope). When the car is under acceleration/load, the entire car starts shaking incredibly hard. When I let off the pedal, the shaking stops immediately. The car can get up to ~30mph without shaking too bad (I can hear the turbo spool up) but beyond that the shaking only gets worse. Acceleration is much worse than normal.

I believe the in-tank lift pump (original) is working, as it makes a normal noise when I turn the key on. The car idles fine (at least to me, while sitting in a windy parking lot in -1 degF weather). With the engine at running temp, it started up fine with no hesitation.

Maintenance history:
Fuel & air fltrs replaced ~8k miles ago
Timing belt & water pump replaced by Guru ~30k miles ago
Suspension replaced ~5k miles ago by Guru
Tires replaced/balanced/aligned last week.

Unfortunately I am at work until 6 pm tonight and can only get on the internet for minutes at a time once or twice. I will try to get my car hooked up to VAG later today or tomorrow.

I would appreciate all the help you guys can give me with a diagnosis.
 

jasonTDI

TDI GURU Vendor , w/Business number
Joined
Apr 26, 2001
Location
Oregon, WI
TDI
20' RAM 3500 CCLB dually HO/Aisan. 2019 Cherokee 2.0T
Look to see if your rubber intake pipe blow out of the intake manifold or backed way out. That'll cause the problem for sure. You need a doggie collar to fix this. Some zip ties, wire or duct tape work in a pinch.
 

jasonTDI

TDI GURU Vendor , w/Business number
Joined
Apr 26, 2001
Location
Oregon, WI
TDI
20' RAM 3500 CCLB dually HO/Aisan. 2019 Cherokee 2.0T
Could be. Would explain the shudder under load.
 

Sooch

Veteran Member
Joined
Nov 13, 2004
Location
Des Moines, IA
TDI
2005 Golf
This very thing has been happening to me when the temp falls below about 10 F. I use a double shot of power service too, but I suspect some gelling is still happening. I think a new fuel filter will clear up the problem, I just havn't got around to doing it.

To the OP, does it clear up once the fuel is up to temp, say after about 20 minutes of highway driving?
 

Ryanr912

Member
Joined
Mar 25, 2008
Location
Brooklyn, CT
TDI
2004 Jetta PD
I already have the "Doggie Collar" installed so that is not the problem.

Fuel gelling is a possibility so I'll pick up some PowerService on the way home and also order a new fuel filter.

The shaking and acceleration did not improve as the fuel and engine warmed up.

Any other suggestions? I really appreciate all the help guys.
 
Last edited:

Ryanr912

Member
Joined
Mar 25, 2008
Location
Brooklyn, CT
TDI
2004 Jetta PD
UPDATE:

While I waited for my new fuel filter to arrive, I drained the installed fuel filter (lots of black particulates) and filled it with Diesel 911. This only seemed to improve the shaking under load for approximately 10-15 highway miles before it returned. I did this two days in a row. My acceleration is back to normal (or close). Cruise control can maintain 75 mph without downshifting up hills.

I installed a new fuel filter and tee (after I broke the first one :mad:) and added a good dose of PowerService (White bottle) to the filter and tank. I filled up my tank with fresh diesel when I was at 1/4 of a tank. Unfortunately the car is still shaking heavily under load, especially > 40 mph. As soon as I left off the "gas" pedal, the shaking goes away.

Have I ruled out gelling fuel? I've confirmed that my lift pump delivers fuel to the filter but could a degrading pump cause these symptoms? Injectors? Tandem pump? Or is it my newly installed & balanced tires? I'm at a loss guys. Any suggestions would be a huge help.

Or maybe I should just bring it to my local Guru :cool:.
 
Last edited:

Sooch

Veteran Member
Joined
Nov 13, 2004
Location
Des Moines, IA
TDI
2005 Golf
Sorry it wasn't something simple. Shaking under load, but smooth while coasting, sounds like you might have one CV joint that is bad. Does the engine hold RPM smoothly in neutral while parked or does it sputter? In other words, if you press the accelerator and rev it up to 2500RPM does it stay there or do weird things, or does this only happen when under load?
 
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