1999 Ford F150 V8 Four Wheel Drive Automatic
I recently took my 99 ford truck up a big hill and came back down, when I got back to the bottom my truck was hesitating to shift. I parked it for like 6 hours and when I got back into it the hesitation started again. It winds out to about 3,000 rpm and goes into 2nd and 3 rd a little hard. It has never done it before only when I go up this hill. What could be problem. Please help.
You sure the tranny is not slipping? If not check below components
Dirty fuel injectors (cleaning the injectors often fixes this).
Bad MAP (manifold absolute pressure) sensor
Bad TPS (throttle position) sensor
Bad or dirty MAF (mass airflow) sensor
Low fuel pressure (leaky fuel pressure regulator or weak fuel pump)
Vacuum leaks (intake manifold, vacuum hoses, throttle body, EGR valve)
Bad gasoline (fuel contaminated with water or too much alcohol)
Sometimes, what feels like a hesitation is actually ignition misfire rather than lean misfire. The causes of ignition misfire may include: Dirty or worn spark plugs
Bad plug wires
Weak ignition coil
Wet plug wires