Jasonsansfleece
Member
Hi Everyone,
As the title says and I'm running out of Ideas.
I replaced a cylinder head for a friend after a Prothe TB failure (I know)
I had Frank06 rebuild the damaged one.
On initial start up the torsion value was -0.5. I adjusted it to +0.5.
Test drive, Engine starts right up, runs smoothly right through RPMs and no hesitation, lurching, but no power at all.
Turbo I say.
Remove exhaust header turbo spins freely.
Assistant (poor owner) starts car and I observe the VNT actuator retract fully and with no load acceleration (on engine stands) actuator moving accordingly.
Pressure test the intake system. Find two holes in intercooler caused by ducting cowl on front face chafing through. These two holes are filled with JB weld whilst new IC is on order.
Re test intake system. No leaks
Tested MAF using VAG-COM. Specified and actual V-close and moving in tandem.
Tested MAP, Results similar to above.
Vag-com says there is 2100 mbar of boost pressure. Is this a theoretical value, I'm not aware of a boost pressure sensor?
You can hear the turbo spooling.
If I connect vacuum pump to vacuum system at the junction on the line to brake actuator, I can draw a vacuum and it will take 15 seconds to leak down.
CEL light does not come on.
As I said, It starts right up and runs smoothly but is with out any power.
If I could not hear the turbo spooling that would be my first guess, but I can and I've seen the actuator actuating.
My second guess is one of fuel delivery. There's enough hot gas to spool the turbo though perhaps a VNT requires very little to get it turning. I also have no experience with this car and therefore dont know how it normally sounds.
Anyway, I would really appreciate any suggestions as to how I might diagnose this further,
Guy
As the title says and I'm running out of Ideas.
I replaced a cylinder head for a friend after a Prothe TB failure (I know)
I had Frank06 rebuild the damaged one.
On initial start up the torsion value was -0.5. I adjusted it to +0.5.
Test drive, Engine starts right up, runs smoothly right through RPMs and no hesitation, lurching, but no power at all.
Turbo I say.
Remove exhaust header turbo spins freely.
Assistant (poor owner) starts car and I observe the VNT actuator retract fully and with no load acceleration (on engine stands) actuator moving accordingly.
Pressure test the intake system. Find two holes in intercooler caused by ducting cowl on front face chafing through. These two holes are filled with JB weld whilst new IC is on order.
Re test intake system. No leaks
Tested MAF using VAG-COM. Specified and actual V-close and moving in tandem.
Tested MAP, Results similar to above.
Vag-com says there is 2100 mbar of boost pressure. Is this a theoretical value, I'm not aware of a boost pressure sensor?
You can hear the turbo spooling.
If I connect vacuum pump to vacuum system at the junction on the line to brake actuator, I can draw a vacuum and it will take 15 seconds to leak down.
CEL light does not come on.
As I said, It starts right up and runs smoothly but is with out any power.
If I could not hear the turbo spooling that would be my first guess, but I can and I've seen the actuator actuating.
My second guess is one of fuel delivery. There's enough hot gas to spool the turbo though perhaps a VNT requires very little to get it turning. I also have no experience with this car and therefore dont know how it normally sounds.
Anyway, I would really appreciate any suggestions as to how I might diagnose this further,
Guy