hmltnangel

Ok folks, going to be a long one so grab some coffee, a beer and a snack

A few weeks ago, I started getting secondary boost issues so I've followed every guide possible for solving them.

The first time I recall any issues, was just after my power steering idler pulley snapped and destroyed the belt. When I fixed this a few days after (had to drive a couple of times without the belt to get to work) and took for a test drive - all seemed well, until a third gear pull. 4500 rpm and I dropped to 3 psi boost.

At this point I done the obvious

Tightened the downpipe (for some reason it had slackened off and I noticed whilst checking things)
Checked all vac hoses for routing and any slits(replaced most of them for good measure)
Checked all solenoids both hot and cold (charge relief wouldnt open when hot so replaced it)

Last night, I decided to tee in my spare boost gauge to the charge relief hose that comes from the solenoid. Now from my workings - the charge relief valve should see that line into the top switch from vac to boost at 4500(ish) rpm. What I seen at that hose was a solid 9.7psi (500mm hg) of vacuum all the way to redline.

Great I thought - its just a dud solenoid.

Before I stripped the UIM back off though I thought I may as well check the other one - so I repeated my test on the Charge Control Actuator top hose - the one that comes from the Charge Control Solenoid. This seen EXACTLY the same results. I know the solenoid is working as the vac drops to zero when the igniton is off on that one. This hose should see the same pressure at 4500 rpm as the charge relief solenoid.

Curioser and Curioser I thought. To double check and make sure my gauge was working fine _ I teed it in with my other boost gauge - test drive and it works perfect.

I then strapped an old cell phone under the hood, with the video recording. The conclusion is - the Charge Control Actuator does not get boost at 4500 rom and I have the video to prove it.

On a roll I thought - hey I might as well strap the dcell to the underneath so it can watch for the Turbo Control Actuator moving at 4500 rpm. The video results on this show - no movement.

So I have come to a shock conclusion that NONE of the four solenoids required to switch my secondary turbo on are working at all.

Car Spec

Power FC
HKS EVC V Boost COntroller - working fine as I can see the precontrol actuator ro move when it should and it holds perfect 10 psi on primary
Blitz Nur Spec catback
Silenced Midpipe
3.5inch SMB Downpipe
Stock Twins
Air COn removed
Air Pump removed - blanking plates are fine
Simplified sequential vac hose setup.
Greddy FMIC and hardpipes/Efini Y Pipe

It was mapped fine up to 280 at the wheels a few weeks before this happened and was running fine.

How can all four solenoid not be sending the signal.

My guessing is going along the lines of the power fc not telling them to change - is this driven by the rpm signal to the ecu?

Something is stopping that signal being sent to switch.

Any ideas folks - help would be appreciated ..... i'm stumped!