After recently replaced all three engine mounts, timing belt, timing belt tensioner, water pump, the two other belts, coolant, and TPS, my 2003 Neon SE has a small idle issue.

Its interesting. It doesn't happen all the time, but it typically happens after at least a short drive. I will pull up to a stop light and after about 2-3 seconds, it starts to develop a rough idle. The idle issue can be cured by a light touch of the gas, or shifting it into neutral. Once this is done, the car can be put back in drive and idle just fine for what seems like forever. All it takes to cure it is a small adjustment (gas or shift). I thought this HAD to be the TPS, but after changing it, Im stumped. Any thoughts?

 

Join the club. A lot of us have had this problem and there are a few different threads on here addressing this problem. Somebody is sure to ask you if you did the torque strut alignment procedure. I know I did and I still had the rough idle. In a different forum, somebody suggested drilling a hole in the throttle plate. I was hesitant to do it, but after trying a lot of other things, I did and it really helped. I started with a 3/32 bit. That helped a little, so I went to a 1/8 bit and it's been great. It's been a while since I did it and I haven't noticed any adverse affects. I figured the worst that could happen is I would have to fill in a hole, but so far, so good.

 

^^ +1. There are dozens of threads with different solutions to this problem. It doesn't bother me personally so I just left it alone.

 

You know I just replaced my crankshaft position sensor and it seemed to resolve this issue for me. Mostly.

 

i idle at like 700 - 800 rpms sometimes 600 and my stering wheel will shake, clean your throttle body and get a CAI it will help, help me and saves gas. not to mention lower temps and emissions. mine rough idle doesn't change when i swich gears on the tranny....i hear its in the steering componets...like gearbox and shaft n things. tourque strut alignment plays a big part too. do you have TILT STEERUNG???

 

How do you get lower emissions from a cleaner throttle body and a CAI? Neither of those have anything to do with emissions...

 

I don't have a fix for you, but I will suggest this: when you come to a stop and the rough idle starts, turn your steering wheel about a quarter turn. This will bump your idle up a little and smooth it out. You must turn the wheel enough to engage the power steering pump switch in order to bump up the idle. Like I said, not a fix but easier than putting it in neutral or giving it gas while pressing the brake at a stop light.

 

lol so apparently we are all sitting at red lights in our Neons, tapping the gas to bring the RPM back up, and we think it's probably just with our car. Strange that this is a problem across the board with neons.

 

I haven't read through every thread about this issue, but I have noticed that most of us developed the rough idle/vibration problem after replacing the mounts and torque struts. I guess we could do a survey, but it seems that most of us used the Anchor mounts. I just compared the Anchor torque stuts to the OEM's. The rubber is much harder on the Anchor mounts. The rubber insert is also much wider than the OEM's. I'm just going to spend the extra $$ on OEM mounts.

 

I have the same issue but haven't replaced the mounts. One of these days I'm going to see what the vacuum is at idle when it's idling normally in drive, and what it's like when the RPM's drop. Might could be a vacuum issue only when the engine is at normal operating temp.