Took my car out to a track day yesterday morning (not on track btw) and it was making 1.8 bar as per normal. When heading home a bit of a pack, including me, started to up the pace a little. In front of me was an R32 (a golf not the good kind) and I thought to myself it must be a bit special as I could keep up with him but wasn't overly held up by him.

That was until I noticed I was only making 1.0 bar peak boost. A quick check of the AVCR revealed everything was still set as it should be but still only 1 bar. I pulled over and checked all the connections and pipework and everything appears to be in good order. That said, I can't hear it clicking anymore where is used to be very noticable.

Is there a common point of failure on these units? I've got mates that I can rob bits and pieces off of to try and eliminate parts but would prefer to try and get to the root cause sooner rather than later.

Oh yes, if it makes any difference the car was re-mapped the last time I used it and convertered to a mapsim. Bad solder maybe???

Any hints or tips appreciated.

 

Check waste gate actuator is connected to the wastegate. Looks like a cylinder with a rod to the turbo. If its come off with the wastegate in a certain position it could be boosting through the wastegate. The solenoid is a bit harder to Test. in theory you should be able to disconnect it and wire a switch to it and a power source and make it "click". Check the voltage on the coil! It may not be a case of using the car battery as power since I dont know what voltage the ECU uses to control it. Usually the ECU just switches the Cars 12V though. Im hust been carefull since i dont wanna get the blame for you burning it out! I dont think it will opperate from the ECU with the car stood?

 

what is the duty cycle reading of the avc-r say during boosting?
and what about the boost reading by the avc-r?

did you check if the avc-r still uses the right setting (a or B) not off?
sometimes the controller can act funny after powerup.

And do you use an actuator of 1 bar? stock is about 0.5 bar

 

Thanks for the suggestions guys.

Its not a standard turbo, its a hybrid garrett gt30. With the acvr turned to off it hit 1.2 bar whist mapping but I remember it ticking when doing this so not sure what was happening there.

I'm afraid I don't watch the duty cycle, just the boost but could take it out and see if it makes a difference. The avcr read the same as the boost gauge and just slightly under what the PFC commander read. And yes, defo set to b but haven't tried a yet, might give that a go. Looks like it'll be a trail and error process then.