i have a 2005 dodge neon that runs rough when at stop signs or lights. its worse when it gets really cold out. put in new plugs and wires, replace all motor mounts. im stummped and dont know what else to look for unless the coil pack would make it do that. other then that i am out of ideas.

kevin

 

This could be a sign that your IAC (Idle Air Control) sensor is dying or dead. I have a manual adjust to set my idle, but I do not believe the 2gn neons have this. I would sourse a spare sensor from a salvage yard or a local car buddy to be sure before making the purchase. Some sensors can a pricey.

 

ok i will do that. thank you very much ghost. i purchased a coil pack yesterday. will see if that helps.

 

they said it would kick a code if it was a sensor. is there a way to check the fuel injectors? are they easy to get to?

 

There is no code for the IAC. I have not used one (and do not need one), as there are other ways to control the idle speed. You can look through the code list yourself. It would likely be associated with a misfire.

 

there are no codes that got tripped. what would cause a misfire?

 

There are no codes because there is no code for a malfunctioning or failed IAC.Misfires are another can or worms.

 

ok i will try a new iac vavle. thank you

 

I had this issue as well last year. It drove me nuts. I had already done the motor mounts, shot anyways. it helped but it was still very bad when at stop lights, especially during the cold and when i had the AC or Heat on (added load to engine). I eventually just took out the air box and filter, unbolted the throttle body.

Cleaned the throttle body with TB cleaner (make sure its safe for sensors), don't forget to open and close the throttle plate via the lever. Don't worry, there is a lot of crap in there. Pool of black sludge came out of mine (had 180k). I also sprayed in some TB cleaner into the neck of the intake manifold (really didn't feel like removing it) and whipped with a shop rag a few times. A lot of sludge came out of there as well.

I replaced the air filter (about $15) and I also added Fuel injector cleaner to the tank, it was $7 so what the hey. Put it all together, let the car air dry for an hour and started it up. Purred like a kitten. The rough idle was 97% better. All in all i spent maybe an hour pulling it apart, cleaning and put back together and waited an hour and spent under $20. always start with easy cheap solutions. You'll learn your way around the compartment that way as well.

I read about the Neons having idle issues with the TB. Partially a computer programming error that doesn't allow the TB idle position to open wide enough. It's nothing that would throw a code, its all in the programming. Some people drilled a mini hole in the TB plate to allow more air in during idle, i didn't want to do that. The car is 97% better, only small shake at idle. It's hardly noticeable.

 

i found a crack not all the way through the intake hose so i ordered one and see if that will help. so they make a sensor cleaner? how many sensors is there? thank you.

kevin