Won't run smoothly in cold weather on 1991 Ford F-150

Have not run a code check yet but truck will hardly start in cold weather and when it does it runs very rough. New battery and spark plugs and wires to no avail. Somebody told me to replace some fuel/choke sensor but don't know where that part is located. Any advise

Asked by for the 1991 Ford F-150
I have a couple thoughts - first the EGR system may be restricted causing an issue for you. This is common on older higher mileage 5.0L V8s. The upper intake has to be removed to clean the passages in the intake. The valve may be sticking too.

Secondly, the Idle air bypass valve may be sticking or causing a problem allowing air into the cold engine.

There are other possible causes too, but I feel like you will be on the right track with this.