1999 (3.8) Windstar Hesitation When Cold

[Terry Southgate]

Hi Guys:

When I start up the Van ('99-3.8 engine) say in the morning (Or anytime after the engine has not been running for a few hours) I put the transmission in Drive and accellerate to say 50 klics, , the transmission is now in high, and I let of the accellerator, the car shudders , hesitates until I give it a little more throttle, then it is O.K. until I slow down a little, then it hesitates again. This all stops when the engine is warmed up. Any Idea's?

Terry

[FordGuy81]

With the engine/tranny fully warmed up, park the van on a level surface. Pull the dipstick for the tranny fluid. Put the vehicle in P or N (use PB for N). Is it at the correct level? If not, top off with MERCON V. I would not use the Mercon/Dextron III blend.

If you have a code reader, scan the computer for 'pending' codes. Codes that are 'pending' are faults that the PCM has found within a circuit, but has not set the CEL yet.

Check the coolant level. Is it normal? Low coolant can affect the readings of the Engine Coolant Temp sensor (ECT). This is the sensor that tells the PCM the temp of the engine. This is different from the temp sending unit which the gauge on the dash reads for temperature. It is very important that this sensor reports the proper temperature to the PCM. Fuel ratios and timing curves are based upon the readings from the ECT.

Keep us posted.

Bill

[tripletdaddy]

Sounds like engine performance issue to me. I'll leave the rest to others. I'd rather not shotgun it with a bunch of possibles when someone else could be more specific.

[terence123cars]

Hi tripletdaddy: thanks for your reply. Sorry, I didn't see your reply until today. The transmission is good, nice clean fluid, proper level, shifts fine. I don't have a code reader, the coolant level is good there is no CEL. The van runs perfectly after it has warmed up a little. I get good mileage and there are no other problems, just this --I would call it "Hunting" after the van has been parked for a while. It seems to happen only at very low throttle settings and I usually feel it when the transmission has shifted into top gear. I actually feel the slight vibration, through the gas pedal. As I mentioned, the hesitation clears up as soon as I depress the gas pedal a little, then when the engine warms up a little more, the hesitation disappears.

Terry

[terence123cars]

FordGuy81: Whoops, sorry I sent the reply to tripletdaddy, instead of you. Thanks for your info. Terry