S4 FC Turbo with HKS EVC not boosting up - why?!
 

ey Guys,

I have an issue I was hoping someone may be able to help with.

I am running a HKS EVC-S Electronic Boost Controller but it just does not want to boost above the stock boost level (6.5psi).

And yet every now and then it does kind of work and boost up.

The other day I had it running comfortably at 8.5psi but had to wind the settings right up to achieve this, then out of the blue it starts boosting to like 12 and 13psi.

Then I take it out today and can't even get it over 6.5psi again!! Farken killing me.

So, what have I checked...

Factory Wastegate Actuator = OK
- Ran 10 pso of compressed air into it via my compressor and it opened and closed freely with no binding etc

Boost Control Install = OK
- Checked the vac line from turbo is plugged in to the correct input on the EVC
- Checked the vac line from actuator is plugged in to the correct input on the EVC
- Checked electrical connections etc on EVC

All good!!

So what the fark, I just don't get it.

I am ready to throw the EVC in the bin and get a Turbosmart Boost T. I had one on my twin turbo liberty and it was great, for $90 you can't go wrong.

THOUGHTS??

Did you buy the EVC new?

If you say that the wastegate actuator is fine and that the install is done correctly, then that means it has to either be the controller or the solenoid malfunctioning. You should be able to test the solenoid by hooking up power to it and seeing if it opens/closes, which should help you figure out whether the solenoid or controller is the source of your problem.

Cool,

I was thinking the same thing.

The actuator and wastegate worked fine when tested, so I am happy to eliminate those - unless it is actual damage to the flap inside, which I can't see.

So the solenoid is testable just with a voltmeter?

Did you set the switch in the back to "SW" (Swing Valve) ? You've got port "O" going to the actuator, port "I" coming from the compressor housing, and port "B" Tee'd into your boost gauge or some similar source?

There are literally two knobs on this thing, there can only be so many things wrong.