would a bad egr valve cause an engine to flood?

 

Possibly, but it could be anything. I see from your profile you have late 80's - 1990 vehicles. Is it fuel injected?? If so the first thing I would check is the temp sensor on top of the intake. Had one go out on my 90 Silverado one time. Dumped fuel into the throttle body like crazy.

 

yes it is fuel injected. i changed out the egr yesterday and it was still running bad so i changed the map sensor and now it is running great!