Hello, would anyone know why an engine would drop in RPM's at a stop light? I have an 03 Neon SXT 2.0 SOHC, and when I first pull up to a light and stop, the RPM's are at about 700 which is where I think it should be, but then it drops to about 500 which causes the engine to drag a little when I want to go. Is this something with the timing belt or would this be more of a sensor issue? I have no additional strain on the electrical system or anything (stereo system, etc.) besides what is stock. Ialso have a scangauge hooked up but it doesn't say there is anything wrong. I'm running out of ideas, but I would like it fixed cause i'm sick of waiting for the power to come when I take off. Thanks.

 

This might be the idle air controller, or something along those lines because mine does it too.

There's been no proven fix as of yet

 

It might be the Pressure steering switch. My Check engine light mentions that, and when i researched what it was, it said that the pressure steering switchcontrols the amount of air going into the block to prevent it from stalling.

but what i do at red lights is put the car in neautral and it stops doing that. when i put it in neutral, it becomes fine.

 

Not sure if it's related, but I stumbled on an article that said the 03's and 04's have a slight bug in their ECUs that can cause problems like this. If you suspect your car may have the symptoms, Chrysler will re-flash the ECU for free with an update. If I stumble across this again I will PM it to you.

 

mine does that too, its weird. if i turn on the a/c it bumps it back up or if i hit thae gas pedal a lil, it wil go back up and be fine. the dealer told me that that is how there designed. but no other car outside a neon does that, that i know of.

 

My sisters 1998 nissan altima does the same thing.

 

Thanks to all for your input! I checked my IAC and the connection wasn't snapped tight, thing is it's also busted so that might be the problem. Ill drive it tomorrow and if that doesn't work ill try other suggestions, thanks again!

 

Ok, so I bought a new Idle Air Controller, New PCV Valve, and got my computer flashed and it still does it. Anybody have anyother suggestions? Would someone know what the LOW-REVERSE BAND is and could that have something to do with the low idle? Could a vacuum leak be a cause? Thanks.

 

Spark plugs, wires. O2 sensor. Maybe the TPS (Throttle Position Sensor) on the side of the throttle body. Last bu not least, MAFS (Mass Airflow Sensor). Shotgun them in that order if needed.

 

Check everything else mentioned in the previous post... If it still does it, drill a tiny hole on your butterfly in the tb... Only thing that ever worked for me.