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Engine Stalls Out in Drive when Headlights Turned on or AC turned on

  • Thread starter Thread starter Tampa Stang
  • Start date Start date Dec 17, 2020
T

Tampa Stang

New Member
Dec 17, 2020
1
0
1
Tampa
Dec 17, 2020
#1
  • Dec 17, 2020
  • #1
Help! I've got a 1965 with a 289 automatic. Car has PS, disc PB, and AC. Car idles fine in park from cold start and after it's warmed up. Idles as it should in drive as well. After the motor warms up (around 15 minutes) if I turn on the headlights it wants to stall out and has rough idle. Seems like there's a "miss" in the idle and sometimes it will stall out on me. The car starts back up again. If I turn the headlights off the car idles fine. If I turn the AC on it will stall out as well.

I've already replaced the voltage regulator, checked the plug wires, distributor cap, changed out the negative battery cable and checked for vacuume leaks.
What are some other ideas I'm missing?
 

65ShelbyClone

Founding Member
Sep 9, 2000
4,675
38
119
Antelope Valley, SoCal
Dec 17, 2020
#2
  • Dec 17, 2020
  • #2
Did you check the battery voltage when it's running and lights are off? How about running with lights on and rough idle?
 

wicked93gs

15 Year Member
Sep 30, 2006
1,198
228
93
Nashville TN
Dec 17, 2020
#3
  • Dec 17, 2020
  • #3
Idle RPM with headlights on and off?
 
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