Hi everybody I'm new to the forum. I just bought my first Jeep it's a 1990 wrangler with a 4cylinder and a 5spd and it has 164,000 miles. The problem I'm having is it runs great with the lights off, but when I turn them on the Jeep studders and barely stays running. I just replaced the oxygen sensor, pcv valve, and replaced the heater core and did the back brakes. It ran fine when I brought home, even with the lights on. I don't know if maybe I knocked something loose under the dash when I removed the heater box or what I did. Any help would be great. Thanks.