Thank you for posting the solution. Too often people don't.

I don't recall ever hearing that cause during my several years on this and other forums.

How did the mechanic figure out the problem? I guess the smoke test did not reveal it because with your foot off the brake there was no leak.

 

Yeah I really didn't think it would be that. But I was watching my fuel trim levels while I was driving and every time I braked the Fuel Trim would shoot up really High. So after talking to the shop and having them drive it they were able to pin point it on the booster.

 

Three cheers for UltraGauge!!!

 

I like to see +/- 5% on the fuel trims. +/- 10% still won't set a code and sometimes that is the best we can get some cars, but it makes me uncomfortable. Anything over +/- 10% needs to be fixed, it will set a fault code.
So yes, your fuel trims are excessively lean.
Do yourself a favor. Get a DENSO or GENUINE air flow sensor. Denso # 197-6030 is the number (197-6020 will also fit)
Clear the codes. Disconnect the battery for about 30 minutes and swap the sensor in the meantime.
Drive the vehicle and after a day or two, re-evaluate the fuel trims.

I've been burned by so many aftermarket MAF sensors, I keep a Denso in stock, because I swap it out first thing before doing any other diagnostics.