It seems to make the motor click and then lose power.
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1998 Chevrolet Express 2500 Question: Why does my engine lose power when I turn on any of my heat climate controls?
Answer #1G. T. Service Center (4244 Answers) , Stephenville, TX - (254) 638-3236ProfessorG October 17, 2013, 20:11Master
What do you turn on when this happens? Defroster?
Replyeekster, October 17, 2013, 20:16Rookie
Yes defrost ...heater..vent...fan on low or high
ReplyProfessorG, October 17, 2013, 20:26Master
Does your A/C work. Is compressor good.
Replyeekster, October 17, 2013, 20:30Rookie
No..not that great...
ReplyProfessorG, October 17, 2013, 20:51Master
Was thinking compressor might be locked up. When the defroster is turned on the compressor also comes on. If your controls are bad during the other settings the compressor might be triggered as well. Should be no other reason for you to lose engine power with heater function. Sorry if I didn't help. If I was close I would check it for you. Need to have someone check it.
Answer #2Greg's Orange Auto (15188 Answers) , Orange, CA - (714) 361-9386globalhelper October 18, 2013, 09:16Master
agree with prof.