2006 jetta tdi mystery problem

tta

Well-known member
Joined
Oct 6, 2012
Location
Florida
TDI
2006 tdi dsg late
Runs fine at mid throttle just driving. Like once you get going. On the highway at 70mph flat driving no problem. No noise. However, on acceleration there is a popping. Sort of like the normal engine sound but louder with an exhaust pop sound.
Accelerating from a stop, there is a serious lack of power. If you accelerate more, there is black smoke. But once up to speed it runs okay.
Unfortunately I am in the middle of a trip. Any ideas?
Thanks.
 

sptsailing

Veteran Member
Joined
Jul 9, 2010
Location
Safety Harbor, FL
TDI
2006 Jetta Manual, stock with Panzer Plate & Franko6 modified EGR cooler & CAM
Maintaining any speed does not require much of the engine's potential power, which means that boost will be minimal. It you have black smoke, your ECU thinks it is getting more oxygen than is actually getting into the cylinders, so is supplying more diesel fuel than required, hence the black smoke. This means more air is passing through the MAF sensor than is getting into the engine. Although I don't know exactly what it could be, some sort of leak in your boost path would create the symptoms you describe. For example, perhaps a small tear in a hose that only opens up at certain pressures might explain both the noise and the smoke. A mechanical close inspection of the various hoses and connections is where I would start.
 

tta

Well-known member
Joined
Oct 6, 2012
Location
Florida
TDI
2006 tdi dsg late
Gaddman,

Good call.

Just popped the valve cover and the cam is shot. Lost a lifter too. It's gone.
 
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