Ok, this problem has plagued me for years. The RX is not my primary driver, but when i do drive it, some times when it gets warmed up, and I am at a stop, trying to go.  There will be no power and a muffled front end backfire/hiccup.  I have to put the clutch in and rev up really high to power out of it.  Maybe related, It could be idling fine, and the just drop 500rpm out of the blue.

 

-Todd

Would an exhaust leak between the engine and manifold  cause or explain the burping sound?

sounds like the maf acting up, or the intake pipe leaking.

A vacuum leak can do that.

alright, i will clean out the air sensor and check for leaks. I'm also go to do a proper adjustment on the throttle position sensor.

Sounds like a plug fouls at idle to me.

Pull plug wires to find the dead one next time it happens.