So this issue has me stumped. Since installing a 3-port and tuning (just to standard at this stage) it i have been getting a wierd idle issue that often stalls the car and results in a p0100 (Maf sensor) fault (fault registers after car stalls).

Car is an Airtrek turbo. Runs a stock boost solenoid which i have disconnected and hooked up a 3 port instead.
3-port is not set to be active under 2000 rpm - It normally does a cycle when you first start the car but thats it. The 3 port is vented back to the intake post MAF.

The sequence usually follows:
Car is idleing like normal
3 port solenoid activates for around 1.5 seconds (appears random)
car immeadiately stumbles and stalls
Check engine light comes on with p0100 code

Any thoughts as to:

Why the solenoid is intermitently activating at idle?

Why activating at idle would cause the car to stall?

 

sounds like the solenoid activates, then somehow triggers an air leak
car stalls, ecu complains about maf being inaccurate

 

Yeah that was my initiall thinking. I figure even with the vented air being plumbed back in, it is loosing too much air too quickly for the MAF.

It sounds like same kind of duration as when the solenoid activates when you first start the engine.

I'm wondering if the solenoid is activating/starting up based on one of the threshold tables like engine temp (which is set quite low at 45 deg).