1984 Porsche 944 4 cyl Two Wheel Drive Manual 220000 miles
My vehicle has begun hesitating while driving and now when I move from a complete stop (tfc light or stop sign). I've even notice the car hesitating/lurching when going up an incline and the speed is around 50-60mph. Not sure if I had bad gas but some have suggested the transmission is slipping. Got any suggestions? The car does not resist when going through the gears and before having a complete transmission job I thought to see if anyone can provide any answers. The vehicle is a Euro spec that was brought back in 1988 from Germany.
Possible Causes of Engine Hesitating or Stumbling: 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