XC90 T6 - Brake Booster Switch & MAF Sensor

[boogyriches]

Hi all, I searched high and low to see if there is any relation to my issue.

I have a 2003 Volvo XC90 T6 that has now become a 'fun' project car, and I am having a few issues. I know that my brake booster vacuum switch needs to be replaced, the last owner epoxied the unit back together so no matter what I'm getting another one. I tried to pull the switch off my 2004 parts car but the minute I touched it, the top came flying off as well as the spring and diaphragm so that's out of the question.

Now my issue is I know I have a working MAF sensor, but when its plugged in the car would stall almost instantly. It will start up and run a little rough then caput again. If I unplug the MAF then it will stay running but of course now I get the P0102 code for MAF sensor.

Anyone else run into this problem? Is the vacuum leak caused by the booster switch strong enough to cause the MAF to malfunction? I do get the air pump running prior to starting and will run intermittently quite a few times after the car is off as well as a quiet hiss.

Would love to get some input on this. TIA

[abscate]

Unmetered air will make the engine run roughly or stall, yes. It doesn’t take much at idle.