2000 Golf with 1.9 ALH, 130,000 miles.
I cannot get any power above 2300 rpm. It behaves nothing like it did when new.
It behaves as though there is a waste-gate that dumps the boost. There are no fault codes stored.
The car cannot go above 75 mph, and struggles to maintain a set speed with the cruise control on. It behaves as though it can’t breathe. At some speeds, the car seems to surge and buck. Most often, it surges between 62 and 65 mph.
It is also very difficult to rev the engine above 3000 rpm when out of gear.
I cleaned the intake manifold this summer. It was down to less than 1†diameter. Upon reinstallation, the engine behaved much better for a couple of months. I was advised to check the air intake connections from intercooler/manifold to the air-box. All seems fine.
I changed the MAP sensor, without much improvement. The VCDS values seem to go above 500, so I presume it is working ok.
I also changed the EGR values, and that did improve the power dramatically.
I have also attempted a check of the VNT vanes without disconnecting the vacuum line or the rod connected to the mechanism. I had the car up on lifts and pumped the brake pedal to bleed off the system vacuum. The VNT vane control would not budge.
I suspect that the VNT is clogged and cannot move, driving the controller into limp-home mode almost permanently.
Is it possible that there is a vacuum leak? I can’t hear any hissing sounds per the video clip on the website.
I cannot get any power above 2300 rpm. It behaves nothing like it did when new.
It behaves as though there is a waste-gate that dumps the boost. There are no fault codes stored.
The car cannot go above 75 mph, and struggles to maintain a set speed with the cruise control on. It behaves as though it can’t breathe. At some speeds, the car seems to surge and buck. Most often, it surges between 62 and 65 mph.
It is also very difficult to rev the engine above 3000 rpm when out of gear.
I cleaned the intake manifold this summer. It was down to less than 1†diameter. Upon reinstallation, the engine behaved much better for a couple of months. I was advised to check the air intake connections from intercooler/manifold to the air-box. All seems fine.
I changed the MAP sensor, without much improvement. The VCDS values seem to go above 500, so I presume it is working ok.
I also changed the EGR values, and that did improve the power dramatically.
I have also attempted a check of the VNT vanes without disconnecting the vacuum line or the rod connected to the mechanism. I had the car up on lifts and pumped the brake pedal to bleed off the system vacuum. The VNT vane control would not budge.
I suspect that the VNT is clogged and cannot move, driving the controller into limp-home mode almost permanently.
Is it possible that there is a vacuum leak? I can’t hear any hissing sounds per the video clip on the website.