I have a 89 dodge D-150 with throttle body injection. Recently it has started to act as though it were a flooding carburetor. If you look into the injector with it running you can see fuel on the air plates . Is really bad at idle but runs good at higher rpm. I have tried MAP and fuel pressure regulator. I also replaced the ECM, but same results. Any suggestions as to the cause?

 

Possibly coolant temp sensor. Check it. You may have two. You want the two wire feller.

 

i would be checking the hall effect sensor. if that isn't it i would almost wonder if it is a sticking injector.

 

Look down it and rev/run it at rpm and see what it looks like. If one is just dumping fuel and the other is spraying it then you know it's an injector. When was the last time you did a tune up(cap rotor plugs)? Any codes?