Chevrolet Repair: Chevy Corsica, poor fuel economy, chevy corsica

Question
I have a 1993 Chevy Corsica that runs rough when idling. uses a
lot of gas and has no power. It was doing this last year and right
when I was going to take it in it just quit and started running
good again. Now its back to to running bad again and I changed
the spark plugs and wires and replaced the coils which came up
as being bad when it was put on the diagnostic machine.
Another mechanic said he thought maybe the problem could be
fuel injectors but I don't want to keep randomly replacing things
hoping to hit on the right thing. Any suggestions?

Answer
I would probably rule out the injectors . If they were bad it would not have gone away, how many miles are on this car and you did not tell me what engine is in the car but I will try and make an educated guess, depending on the engine in your car the 1st place I would probably look from what you have described is the IAC motor ( Idle Air Control) it is located on the throttle body on the V6 engines and these tend to get dirty over time and need a good cleaning and or replacement, a bad IAC will cause a lousy idle and poor fuel economy, I would also look into having the catalytic converter checked ( power loss ) and the O2 sensors, a blocked or partially blocked converter can also cause your above mentioned problems, especially a loss of power while driving or under load, I hope this helps and good luck, let me know how you make out'

Steve