Same thing is happening to me... Only thing that is weird is that I Replaced all my vacuum hoses with a kit from LCE Engineering and still the problem persists... Im at a loss as well.
what kind of gas mileage are you getting?
I was gonna do a vacuum hose kit next too, I've gone around my vacuum hoses with carb cleaner and sprayed around looking for leaks but found nothing
I'm so tired of searching for the root of this problem.
Mine is 3.0 V6, manual transmission, 99% of the time i'm in 2 wheel High. i'm getting 320 KM to a 57L tank (200 miles for 15 Gallons) = 12.5 MPG.