I have a Contour 95 GL with 65000 miles on it. Descent car though with some funny "features" in it's engine. I've been having a particular problem and I was wondering if anyone encountered it. When the engine reaches the normal operating temperature, after one accelerates and drops the accelerator to switch gears the engine keeps increasing the rpm's upto about 4000, keeps them there for several seconds and then drops. I had problems pinpointing exactly when this happens, since the problem is not persistent, although it happens most of the times. It looks like, in particular, this happens more when it's hot outside. Can it be the mass airflow sensor or the air temperature sensor? Another problem, that might be related to the one above, is the "hesitation" when accelerating slowly. It looks like the engine is lacking power, even at 2000-2500 rpms. Then at about 3200 it abruptly picks up power. I tried replacing the fuel filter, doing the fuel injector cleaning. Does not seem to help much. Thanks, folks...

The car has a 2.5 V6 engine. Actually, I tried cleaning the flip-flop in the air intake duct. It had lots of dirt and that seemed to help the problem somewhat (even though they cover it with protective material which should prevent dirt buildup, however does not really help). If the problem becomes less obvious I'll try cleaning also the idle speed sensor duct. Did anyone have problems with idle speed sensors?