I seem to have an intermittant hesitation/surging problem in my 97 4.6L 5speed. The truck will buck at part throttle and accelerate like the engine is being starved. It idles fine and does not buck at very light throttle application. Vacuum problem?? But, since the check engine light does not come on, I was thinking something mechanical. Spark Plug Wires?? I have used Techron FInj cleaner and replaced my fuel and air filters, seemed to go away for a few days and has now returned.

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1997 F150 4.6L 5speed SC 4x4

 

ttimoney,
Save the aggravation and effort and go ahead and have it put on an analyzer. Todays motors run as well as the sensors tell it. There is really no way of knowing for sure which sensor could be bad. Sensors are known to last forever or no time at all.


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2000 Sport,Black,5.4L, 3.55 LS,Rear 2in drop, Gibson Super truck, K&N.
86 5.0 Mustang LX w/off road h-pipe, Borla catback, FMS 65mm TB, K&N, Mac Racers choice shifter, MSD-6A,180 Degree thermostat,14 Degrees timing

 

I had that on a truck and it ended up being the 02 sensors. I replaced the sensors, which had not set any codes, but I saw a terrible decrease in gas mileage.

Like 2Fords stated, I would have it put on a scope.

 

Are you talking about when the truck "lurches" while you are moving? Mine does it in the middle of 3rd gear a little. Especially after I drive it a while.

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'97 F-150 XLT Clearcoat Red
4x2
4x4 wheels
Stepside, K&N, bedliner
32inch tires,flowmaster
tint, matching ford sticker
5spd fully loaded, hidden hitch
Comming soon:
spark plugs/wires,leveling kit,toolbox,
bed rails,push bar, CB with whiplash,
clear corner lenses,brush guard, blackouts,
edlebrock shocks, hypertech, K&N induction system,KC highlighters,
bed xtender, BOSE audio or infinity gold, disc changer,
side steps, dixie horn, white faaced gauges, and those small fender flares some 4x4's have,
matching boddy color of course, and some of those door guards,ventshade visors, power pulleys, that is all
i can think of right now

 

Thanks for the quick replies. The hesitation happens in any gear and is at its worst when at a low (2000) rpm and moderate throttle. I guess the easiest thing to do would be to have it scoped.

Tom

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1997 F150 4.6L 5speed SC 4x4