My check engine light is never on, but my car still idles rough, any suggestions?, B4 I replaced the IAC the light was on, but after i changed it, it turned off. It runs fine when it goes down the road, only runs rough when engine is at idle? idk what to do with it, i don't have alot of money to spend (I'm only 17) and i would like to know for sure if the MAP or Throttle position sensor were actually bad b4 replacing them. Any way to really tell if they are shot? Also, the guy who sold it to me had taken the Catalytic converter off and i was wondering if that can really kill gas milage, i know it will hurt it but this is really bad I've gone about 190 miles on 2/3 of a tank, and you guys know thats a 20 gallon tank. OUCH! that doesn't seem right, and the exhaust smells like the car is burning really rich,( or is that what its like with no CAT?, Also would changing the EGR valve and O2 sensor help at all if there is no check engine light on...... what other things should i look at to solve the problem...

I know you guys are probably sick of hearing me complain about this idle problem, i just think some of you guys are experienced enough to help me out a little, I would hate to bring it to a mechanic and pay him a bundle to fix something i could do by myself.....

Thanks Guys!

 

I was wondering if a injector could be plucgged up a little..... It sat a little while before i bought it and i was thinking maybe when its at idle it sputters a little because the injector is not performing great and when i get out on the street it gets more pressure and its alright?... or is that stupid?? It's just a thought i had?