bogging at idle with heat on

[cinaibur]

My 98 XLT started this just yesterday. When I am at idle with the heater on, I hear a click coming from the engine bay. When the click occurs, the lights barely dim, and the rpms drop from 500 to 400. It only last for a second and the car doesn't die. It hasn't affected how it drives. If I'm at idle, it probably happens every 5 seconds and only lasts for a brief instant.

 

[RomeovilleIL]

As part of the defrost functions the truck is running the ac compressor. Normal operation.

 

[dmyers87]

If this is being a real problem for you, go into the fuse box next to the steering wheel & pull the fuse for the air conditioner. That's what's kicking on and off causing this. Your idle air control valve sounds like it's going out. Try taking it off, its under the top engine cover on the sohc 4.0 held by 4 7mm screws, & cleaning it with qtips. If this is the issue it'll act normal for a minute then return to the bogging down. Rockauto.com has the cheepest price on them, depending on what exact one you need.