'92 Ranger 3.0 with very rough idle problem

My high mileage fuel injected Ranger suddenly began idling roughly two days after I changed the plugs, wires, and filters. It also is making kind of a "whining/whirring" type noise which is coming from around the distributor area. I triple checked the plugs and wires to make sure they were installed and ordered correctly, but I am still getting the rough idle and the noise from the distributor area. It was running like new for two days after I did the tuneup. It seems to run OK on the highway and the check engine light occasionally goes on and off. Anyone think it's a distributor problem? An IAC problem? Many thanks in advance.

I don't know if it applies to your year truck but my OBD II states that although a steady lit Check Engine Light (CEL) indicates a problem, it is not critical in that you may continue driving until the problem can be taken care of. However, a flashing CEL indicates a more serious problem and for the operator to safely but quickly come to a stop.

If you have an ignition problem you are going to know it. When I had the noise (more like loud humming during idle) similar to what you described, I replaced the Idle Control Valve and it corrected it.

I don't know if it applies to your year truck but my OBD II states that although a steady lit Check Engine Light (CEL) indicates a problem, it is not critical in that you may continue driving until the problem can be taken care of. However, a flashing CEL indicates a more serious problem and for the operator to safely but quickly come to a stop.

If you have an ignition problem you are going to know it. When I had the noise (more like loud humming during idle) similar to what you described, I replaced the Idle Control Valve and it corrected it.

Thanks for your help. I'll look into the IAC valve.

With the engine running, and your hand on the distributer, can you feel anything that seems like the noise source? Like the cap not seating well,or a bad bearing?