After my truck warms up, and around 4 miles of driving, it starts to run rough when it comes to a stop. It shakes up and down while at idle and eventually stalls out.

I'm thinking the problem might be either the map sensor or the EGR valve. Do you guys have any suggestions?

(My truck is a 1992 S-10 Chevy with a 4.3 engine.)

Thank you!

 

Check your egr. If it isn't clogged and all the vacuum lines are working correctly then check and or replace the high temp sensor on the top.of the intake manifold. It's right next to the thermostat housing. If its not working correctly then the truck will still think its cold therefor richening the mixture when it needs to be leaned out. Causing flooding and stalling. Hope this will help!

 

Catalytic converter will give you similar problems. If the EGR doesn't fix it, knock the exhaust loose and see if the problem goes away.