random stalling / won't restart

'91 Sunbird 2.0 eng., car runs great, then it will randomly die as I'm coming to a stop. Won't restart unless it sets for several hours. Have replaced plug wires, cap / rotor. Also replaced oxy sensor, and coolant temp sensor. Cleaned IAC Valve. No cat. This happens randomly, some days it happens, then not for several days. Does it sound like coil, or module, or maybe needs a new IAC ?

At a loss what to do next. Thanks

it sounds like an ignition module failing due to heat.

OK, we gave up on this one for a while, let it set, now it will not start and I found it is not getting any spark. Any way to test which component is bad? I figure it's either the module, or the coil pack.

Thanks

I agree with Rich. The ignition module is bad and needs replaced. Try one from a wrecking yard. They are cheaper and if it doesn't fix the car you aren't out that much but I bet it will start right up with another one.

Sounds like a plan, I'll post results when I get the module in. Does the distributor need to be removed to replace?

i had a problem with my car once and i had istalled a tach on my car and had to splice into the ignition wire on a plug. check the wires cause i found out mine were broken at the top of the plug so i had to cut into the plug to get more good wire then i just soldered it back together. so check the ignition wire. even try ad see if it is getting any power