I had the air cleaner element (stock GSL-SE) out, and while it was idling, I put my hand over the air intake opening (approx 3" x 4") to feel the air intake flow.

Did not feel much air flow. SO, I took a rolled cloth and covered the intake, expecting it to stall. But it did not change and continued to idle perfectly. Held her on for 30 seconds and made sure it was covering the opening too. Still idled perfectly, maybe a little slower...
A quick inspection of the intake components found everything in order.

SO where was the air coming from?

I presume the air flow meter operation would not be accurate if air is going around it somehow.

Any thoughts?

 

bump

 

Air bypass valve... Let's just enough air go through/around the throttle plates to keep the engine running at idle. If you were to try the cloth trick then romp on the gas real quick, you should feel a vacuum...

James

 

Thanks for the input spot skater. I agree if I romped on the gas I would likely feel a vacuum.

Any other thoughts?