Hi everyone, yesterday I noticed that my 2006 G35 sedan was idling weird, as if there was an ignition or fuel problem. What my car does is when I am slowing down for a red light (or stopped at a red light), once the rpms drop below 1000, the engine "shudders" for a very brief moment, less than half a second. Another way I can describe this "shudder" is what lawnmowers do when they idle, they have those brief moments where they don't run like they should. The number of times this happens when stopped for a red light can be anywhere from 10 - 25. Just this morning when I was stopped for a red light, the engine "shuddered" 23 times in a 2-minute period. The car has 145,6XX miles. Anybody know what this could be? No check engine light and no codes when scanned with an OBDII reader.

Dirty air filter?

When is the last time you changed it?

Telcoman

I've had this same situation happen. Its not regular enough for me to be seriously concerned with it, but I'm investigating it.

I had same issues with low idle. I bought a can of throttle cleaner and MAF cleaner. I sprayed and wipe the throttle clean of carbon buildup, and gave the MAF a good clean with the spray. Now it runs at higher idle as it should.

I also spent the time to re-torque all the plenum bolts.

telcoman wrote:Dirty air filter?

When is the last time you changed it?

Telcoman

The air filter is not dirty. I don't know the last time it was changed since I bought the car used in mid-March of this year and it wasn't very detailed on the CarFax.

raremotive wrote:I had same issues with low idle. I bought a can of throttle cleaner and MAF cleaner. I sprayed and wipe the throttle clean of carbon buildup, and gave the MAF a good clean with the spray. Now it runs at higher idle as it should.

I also spent the time to re-torque all the plenum bolts.

The idle is not low, the idle is actually high; it idles at 875 rpm when the car is up to operating temperature while in Drive with the A/C on. In Neutral, the idle is around 950 rpm. I took the intake tube off to re-torque the valve cover bolts to help slow down the oil leak and I believe I cleaned the throttle body. I didn't clean the MAF sensor because it didn't look dirty. Maybe I should clean it and see if that makes any difference.
I'm surprised that no one suggested an engine mount causing the engine to shake. The passenger side mount has fluid leaking out of it, which I think is what is causing the car to shake.

Hi everyone,

Just an update, today I received an engine mount for my G35 and I will probably swap it out tomorrow. I will let you all know if this fixes my issue with the "semi-rough" idling.