1999 Ford Expedition 1999 Ford Expedition Stalls Immediatel

JASONB6

MEMBER
1999 FORD EXPEDITION
V8
4WD
AUTOMATIC
98,000 MILES

My Expedition began stalling during damp/rainy weather immediately after starting (2-3 seconds). I I changed the fuel filter, air cleaner and cleaned the MAF with MAF cleaner. The vehicle started but ran rough. I found a vacuum leak and replaced the affected section of hose. The vehicle starated and ran great but I could hear a "put-put" noise coming from around the 3rd cylinder on the passenger side. I can feel a tap when I place my finger on top of the coil pack for the 3rd cylinder on the passenger side. A mechanic told me the noise was a slight valve tap and not to be concerned. However, the sound does not increase in speed with the motor during revving/idling. The car ran for a week during dry weather but would not start recently during a rainy day. I am thinking it is either a faulty MAF or coil pack. Any ideas.

1 Reply

RASMATAZ

MECHANIC
75,992 POSTS

Wet or Dry conditions if it refuses to start do below to determine if its a fuel or spark problem

Get a helper disconnect a sparkplug wire or 2 and ground it to the engine atleast 3/16 away from ground-have helper crank engine over-do you have a snapping blue spark? If so-you have a fuel related problem, check the fuel pressure to rule out the fuel filter/fuel pump/pressure regulator and listen to the injector/s are they pulsing or hook up a noid light. No snapping blue spark continue to troubleshoot the ignition system-power input to the coil/coil packs, coil's resistances, cap and rotor, distributor pick-up coil, ignition control module, cam and crank sensors and computer Note: If it doesn't apply disregard it and keep testing