[kena]

Particularly during colder weather40'ish versus 60'sh my 914 won't run smooth when I turn on the headlights or the rear blower for heat. Also the engine RPM's drop about 500rpm when the load is placed on the electrical system. Headlights on..rpm's drop...headlights off..rpm's increase. The car bucks and hesitates as if the throttle position sensor is malfunctioning. It improves a bit as the temp reaches the 180 mark. I believe the TPS is malfunctioning due to the voltage drop when the lights or heater comes on. Do I have an alternator problem(I recently replaced the voltage regulator) or is it possibly something else like a bad ground strap? The alternator seems to be working ok. My lights stay steady at idle unless the idle goes below 600rpm then they dim and the radio will shut down temporarily until the idle speed increases. What should I be looking for?