I have noticed that in park with the car idling that the note/pitch is slightly irregular every now and then. Nothing abnormal noticed once the car is in gear. How normal is that for these cars? I'm coming from a corvette which was always irregular (totally normal) and an e46 that was never irregular without a problem.

Keep in mind that I'm an engineer and very nitpicky. I haven't started pulling things apart to check plugs and cables yet. The car has no codes and the only mod is an Injen dry cone intake. My suspicion, if it's not normal, is that it may just be the intake causing the car to run a little lean.

 

Well on my previous cars when Idle wasn't stable I would usually clean the throttle bodies behind the intake pipe.

I hope that's what it's called.

similar to this: http://g35driver.com/forums/v36-diy/...le-bodies.html

possibly your cone filter has let some dirt in?

 

It's worth a try. Yeah throttle bodies, vacuum leaks and idle control valves are generally a culprit. The rpms don't really change enough to be noticed on the tach. It's just a slight audible difference.

 

I got my injectors and throttle body cleaned while my car was at the dealer... Purrrs like a kitten now

 

Check your battery, the only time any of my cars especially after sitting for I, was actually do to failing power source. If battery is dying internal resistance too high, cannot provide enough voltage for ignition or comp to function correctly.

 

This. This is common across the entire Toyota line and has been for many years.

 

Interesting. This is the only japanese car I've had aside from an eclipse. Even if the battery gauge reads around 12-13? I think. I'll check when I pick up the car tomorrow

 

this

both my '09 and '13 have done this

 

Well, hope that helps.

TORXUVIN: NOTE: You can have a failing current source, aka battery, and it still may read 12-13 volts under minimal load because the voltage is directly proportional to the current and resistance. ....

 

That's a good point. Just picked the car back up. It's reading right at the middle of the battery icon. I will check the date though. I'm assuming it's an original battery. 5-6 years is generally a decent lifespan.