Boost question R

[Nev]

Mine is a digital guage and it reads -11psi which equals -22inHG on hot idle

Yep, that's what I'm reading, allowing for my gauge inaccuracy, (or eyes that can't differentiate enough).
I have another gauge that reads +vePSI and -ve inHg but it needs power feed so haven't plumbed it in yet.

Checked all pies again, still no leaks. Checked connectors, seem fine.
Unplugged TCV, and still have same boost, so now points to

1. New TCV from volvo is faulty
2. Signal not getting to TCV from ecu
3. Broken wire in cable to TCV.

No time to check tonight with multi meter to see if I'm getting power to TCV. Do these TCV's click when powered up with the ignition as vauxhalls and saabs do? Will be quicker than a meter if they do..

[LeeT5]

Yep, that's what I'm reading, allowing for my gauge inaccuracy, (or eyes that can't differentiate enough).
I have another gauge that reads +vePSI and -ve inHg but it needs power feed so haven't plumbed it in yet.

Checked all pies again, still no leaks. Checked connectors, seem fine.
Unplugged TCV, and still have same boost, so now points to

1. New TCV from volvo is faulty
2. Signal not getting to TCV from ecu
3. Broken wire in cable to TCV.

No time to check tonight with multi meter to see if I'm getting power to TCV. Do these TCV's click when powered up with the ignition as vauxhalls and saabs do? Will be quicker than a meter if they do..

I doubt all the above. I think you maybe looking too hard or even barking up the wrong tree. I think you need to take it to the dealer so they can run live readings and make sure things are doing what they're meant to.

[LeeT5]

Nev, have you got to the bottom of this?

I believe I too may have the same problem. Need to do some more checks but at the moment I'm only getting 7psi boost WOT in third gear across the rev range.

[LeeT5]

all sorted now. Was my new TCV. Slow learner!