Rough idle, temp gauge

[jh1104]

Problem one

I have a nice little 91 Loyale wagon 5 sp.  I starts great, runs great except at an idle then it is very rough but as soon as you put some gas to it, it smooths right out.  There is a solid check engine light on.

 

Problem two

I dont get any reading on the temp gauge, again it runs fine, has plenty of fluid gut the gauge never moves and I am not sure the fan comes on, I don't hear it but I have not put the hood up and let it run to actually see if it comes on.

 

Thanks for the help

 

Jeff

[PA Grown]

Check temp sensor on the radiator make sure all connections are good. The rumble at idle definitely sounds like a bad spark plug.