Ignition control module problem?

I'm new to the site and need some help. Just bought a very stock '91 B2200 with stock carb. When I bought it the idle was high but otherwise it ran very smooth and drove really well. The idle was turned down and it continued to run well. Then it began to intermittently die but then it would restart if left alone for several minutes which made me think it was flooding. Now it won't start at all even with a small squirt of starting fluid. I pulled a wire and stuck an old spark plug on it. When the key is turned on it sparks well. When the key is turned to the on position I get no spark. I have talked to mech's in the area and both thought it may be a bad Ignition Control Module. Where is this located and how is it tested. Once again the truck started well and ran smoothly right up until it started this mess. Anyone have a prob like this? Truck has 2.2 litter with 5-speed. Thanks for help.

I can't understand your post completely, but I'm thinkin' the issue is the ignition switch. When it won't start, or it dies, leave in the "on" or "run" position, and see if the coil positive side is getting 12 volts positive (on its positive side). There are at least three contacts in the ignition switch that are separate for "run" as opposed to the "start" position. So it can spin the engine great, and still be a bad switch. And these switches are only good for about 15 years on B-trucks.

If its what I think he is talking about.. its under the dist. cap iirc but no idea how to test it.

Hey, thanks for the tip. I'll give that a try tomorrow and will post the outcome.

Test the electrical part of the ignition switch first, your symptoms align with that. When it's "not working" see if you get positive voltage to positive side of the coil. If not, bad switch.

If OK, then explore further such as ignition module.