VW Golf TDI Lag Problems

[vanurdi010310]

VW GOLF GE TDI PD 150 - 139,000 miles

I have just had the top half of my engine rebuilt as the Cam Shaft had worn. At the same time the garage changed the Head Gasket, Cambelt, and skimmed the head. They found when they test drove the car there was no power till 4,000 revs. All 4 injectors were
then be changed. They then said everything was fine.

When I got the car back I found there was no pull/power till 2,000 rev. The car used to take off like a rocket in low revs as it had been remapped. Also in 6th gear around 70MPH the pull has reduced and so has top end speed.

Is there anything else that could need changing or could be at fault/damaged like delivery of air, fuel or engine management ect? The car had a remap about 5 years ago so could this be the problem after the rebuild?

The car also need 2 attempts to starts at the moment.

[HellDiver]

Sounds like it's not timed properly. If it's a little out (slack tensioner, or off by a tooth) then it'll run like crap and be difficult to start (see the thread about the Combo 1.3CDTI in the Vx forum here).

[vanurdi010310]

Somone stated this to me. Is this what you mean:-

The fact you've had the head removed and the cam replaced suggests to me that the garage has NOT set the camshaft timing correctly -- they may have it one tooth retarded on the cambelt. I'm not certain but there may be adjusters on the camwheel too to dial in the timing correctly.

[XitUp]

Also, that sounds like boost threshold you're talking about, not lag.