Heya people,

To start i have a 1999 eclipse GS (420a). I have a AEM CAI, Greddy Header, and Custom Cat Back 2.25 Exhaust. A couple months the problem started when my car started misfiring. I replaced the plugs, and wires. That didnt stop the misfire so i went back in, and replaced the plugs, wires, gromings (is that what the are called? the round gaskets that go around the plugwires under the valve cover), valve cover gasket, and the ignition coil. Ever since then i have felt like the car chugs, but i have not had any misfires. The car seems to run fine and doesnt ever stall like a misfire or anything. When the car is at idle that is when it chugs, it does it when its in gear or in park. My car idle jumps from about 500rpms to about 750 rpms depending how long it has been running. Now i was wondering what else could be causing this chug sensation. Im thinking the Catalytic converter so im gonna take that out and put in a test pipe. Also when i put my exhaust in they put the o2 sensor back in behind the catalytic converter so im gonna have that taken out and tied up on the exhaust. Since this is currently throwing a CEL would this be causing the chug? What are some other things i should check? Air Filter? Gas Filter? Any input would be greatly appreciated, this is really starting to get to me. Thanks for all input.

*Edit* The chug sound is loudest when you put your head down by the passenger side headlight and front tire.

Travis

*Bump*

No input? :(

welcome to the club!

considering you have corrected any ignition problem, the next step is fuel. change the fuel filter and see if that helps (its preventitive maintence anyway, so its worth doing anyway.

next i would check electrical. make sure the battery is good (a/c ripple not filtered by the battery or that produced in excess by the alternator can cause a wierd idle), and that the terminals are clean and secure.

im not sure, but its possible you have an exhaust gasket leak causing the "chugging" sound. this is probably unrelated to the idle problem, just a symptom.

or, you could be like the select few eclipse owners who are just naturally blest with poor idle. :shrug

Originally posted by er00msivarT
*Edit* The chug sound is loudest when you put your head down by the passenger side headlight and front tire.

maybe in the timing belt cover, like the water pump or tensioner pulley bearings. that happened to me when the bearings were completely SHOT.