Engine Mechanical problem
1999 Ford Explorer 6 cyl Two Wheel Drive Automatic 134, 00 miles
after diving my 99 explorer long distances in weather hotter that 85 deg. F, the act like there is no fuel, and it run bad. I have to let it 'cool' down for 45min, then it will be ok. It mostly does this on long trips on highway, not in the city. Fuel filter has been changed. Checked the codes and they say lean on bank 1 and 2. Or the code reads miss fire on #1. Since when you clear codes it gives different codes but not together. Is it vaporlock or something else? There is a loud humming sound from engine compartment when it gets hot too. Sounds like a vacuum cleaner not a vacuum leak. The MAF sensor has been changed too.
The Ford Explorer uses an idle speed control valve that allows air to flow thru the idle air passage inside the intake manifold. This may be the problem. When this air passage gets clogged up with carbon or grime it restricts the passage & the result is a loud humming / moaning noise. The repair is to remove idle speed control valve & spray carburetor cleaner or intake cleaner thru air passages inside intake manifold & clean or replace idle speed control valve.