I have a 2002 Explorer Sport Trac, 4.0L 6 cylinder. It has 66,000 miles on it and I have been experiencing an engine stall. It basically has a feel of loss power and will only accelerate to 3,000 rpms before it stalls out. If I am on a flat road it will gradually build up to 40-45 miles an hour but if I press down on the accelerator past about 1/3 of the way down the engine stalls out and it loses power.

Today it happened after I had driven it to work. I had our mechanic at work put it on a computer and the "Check Engine" light does not come on (when tested at first start up the Check Engine light comes on) and the computer did not register any diagnosis codes. When I got in it to come home the problem had gone away and the truck ran fine.

Any help with what this might be will be greatly appreciated.