Hi everybody,


So here's my strange / intermittent problem.


In higher RPM's the car doesn't pull like it should.
I can hear the turbo spooling, the blow off going off, ... but not as it should. Maybe a bit too quiet. And everything goes way to slow.
What is visible is, let's say I go from 2nd to 3rd, when engaging 3rd let's say I am at 5000rpm.
What happens when everything is normal, the RPM's start at 5000 and go up.


When I have my problem, it goes at 5000 when I change the gear, but then goes down to 4800 (like a loss of power) and then goes back to 5000 and up. but really not pulling as it should.


And like magic, once I had this weird hissing sound under the bonnet while driving (psshhtt) and after that everything when back to normal. 5 minutes after I had the same problem again.


MAF, fuel pump and filter have been changed recently. Also the injectors have been cleaned.


I guess it can be a lot of things. But where do I have to look?


Thanks in advance,
Ben

 

split vac hose ?

check the hoses and clamps listen for air leaks identify and replace

 

Id be checking for leaks from the charge air hoses, maybe loose clips or splits in the hoses. Check the hose that goes out the turbo into the back of the intercooler and also the hose that goes from the intercooler into the throttle body/intake manifold.

Also consider the BOV/Dump Valve, is it a recirc or vent to air type? Check the hoses on it. The pressure seal inside the BOV could of failed so its leaking boost pressure/charge air when it should be sealed. If its a recirc type check the hose that goes from the BOV back to the intake.

Faulty Boost pressure solenoid valve? Normally mounted to the left in the engine bay by the strut mount or may be mounted on top the intake manifold itself under a little metal cover. Depends on model of scooby.

As sti-chris says, it could also be coming from the vac hoses so check them too.

Either way, it sounds like you have air leaking somewhere.

 

I think I found the problem.
There was a split in the gasket between the turbo and the up pipe leaking some exhaust fumes.
The bottom gasket was gone too.
Will be replacing everything soon (together with new bolts and nuts)