Hesitation, I'm Stumped ??

[explore97]

This has got me stumped, my wifes 97 AWD Explorer has a slight hesitation at speed. Its an automatic 4.0, the hesitation feels like a small bump in the road, just for a spilt second. It happens at diffrent times,sometimes at cruising speed, 60mph, sometimes around town 35mph to 40mph. I have changed plugs, tranny fluid and filter, used fuel injector cleaner several times, and a new fuel filter. It doesnt do it everytime, I dont know what to do now or should I just let it go till it gets more noticble, any suggestions?

 

[V8BoatBuilder]

You sure it's not a V8 5.0? Those were the only AWD explorers.

You are feeling an intermittant missfire, I had the same problem in my V8, new spark plugs and wires cured the problem. Use platinum plugs, I've had bad luck with coppers.

I would change your wires, the ends are subject to a lot of heat from theexhuats manifolds.

 

[explore97]

Positive its an AWD 4.0, I put Ford Motorcraft platniums in already that was way before the stumble started. The wires are the orginal ones from the factory. I guess I could change them and see what happens they do have 120k miles on them but they look brand new.

 

[V8BoatBuilder]

I had 115k on my wires, they looked new as well. Life for wires is about 60-90K at the most. I'd start there.

Do you have a switch on your dash that says "4auto, 4hi, 4low" If so you have a "Control Trac 4wd" system, which is not AWD.

 

[explore97]

Yes I do have that switch,thanks I guess I'd better do the wires next.

 

[Opera House]

I've had numerous stumble problems on my 97

It was always defective plugs. Sometimes in as little as 4K. I have found four times that a crack appeared on the insulator under the boot. I believe this is because of an arc traveling under the boot when there is insufficient or contaminated dielectric grease. I finally bought a set of new wires (first time for any car in over 25 years). I usually just clean them but previous owner had pulled on the wires tearing the insulation.

 

[ManixT]

Have you tried Dead Link Removed

 

[explore97]

Yes, I have cleaned it. I'm going to change the wires next to see what happens.

 

[Billy177]

try a new fuel filter