My 1992 Ranger has a 2.3L 4cyl 100hp engine with 207k miles. It occasionally hesitates when beginning to accelerate but never when at idle or when driving at speed. I don’t even know where to begin. The engine has had consistent maintenance and runs well otherwise. This hesitation makes me afraid that it will damage the drive train somewhere. I’d like to at least know what the problem is even if I can’t fix it myself because I’ve done most of the work on the engine. Thanks for the help.
The drive train should be fine. My guess is that your problem is rooted in the inability of the engine to properly meter gas, resulting in a temporary “lean out” when you hot the pedal, similar to what was common in old carbureted engines.
Unfortunately I’m unable to access repair information for this vehicle, but if this is a throttle body injection system, I’d look to the throttle body. You may have more than one injector, one to add spray to accelerate, and that one may be gummed up.
Post back and let me know if my guess about it being TBI is correct or wrong.
Just saying “consistent maintenance” is way too vague. What has been serviced and when? E.g. until I knew that the spark plugs and wires and fuel filter are nearly new I wouldn’t start to speculate about anything else. Very often that kind of initial hesitation is just an ignition system problem - old plugs & wires / coil pack starting to go.
On a 92 I’d guess the EGR system may be malfunctioning. 2nd up would be the throttle position sensor. Improper idle speed, ignition timing, or air leak into the intake manifold are also possibilities.
If this were my truck, rather than guess, I’d bring all the routine maintenance up to date, including having the idle speed and ignition timing verified, and have all the diagnostic trouble codes (current and pending) read with (preferably) the Ford specific scan tool before making any assumptions.