Is 500 rpm too low for idle?
I am wondering if this is normal or I have something I need to look into. While in park or neutral it idles just fine around 700~800 rpm, its smooth and quiet. When I put it in gear or when I stop while driving, the rpm drops to around 500 rpm and it shakes and causes the whole truck to vibrate. I assume that is because of the low idle. Its not pulsing, missing, or erratic, just a steady vibrate. I am wondering if that is normal, or its idling too low, and if it is too low what to look for. The pcm is not reporting anything so I assume the sensors are fine. I just got it a couple of months ago and its the first jeep I have owned so I am not sure if its normal. (its a 4.0 I6) Thanks! - Jeremy