My 86 Eat cause it to do this?FI 302 has been ideling rough when warm for about a year now and it misses and will surge and sometimes die. I read on another post somthing about the exaust. The exaust cross over tube is broke at the back of the engine Would this cause bad idel? How much is that assemboly from a muffler shop and what do I ask for?
I have new
fuel filter
air filter
water pump
Someone mentioned a IAC how much is that?

 

Check all your hoses for vacuum leaks. Then take the egr valve off, and clean it out. To see if the egr is the problem, you can make a temporary solid gasket to block it off, and then see if it idles better.