My 1997 F150 5.4 check engine light came and>
While idling or in Park the RPMs will drop below 500, then the RPMs will jump to about 1100 and then back down constantly,my gas mileage is terrible. On my way to work today the check engine light started flashing (continuously), and when I would accelerate it felt like I was on a gravel road until I reached the speed-limit then it seamed fine, excluding the flashing CE light??? Many Thanks in advance for any help or advice.