Normal idle RPMs? Also possible exhaust problem?

[jeremywitt]

The reason I am asking this question is because my 2003 Durango Idles at about .5 RPMs. Seems rather low but I am not sure.

The exhaust thing has been bugging me as well. Actually I'm not sure that it's the exhaust but my truck sounds like a beat up old farm truck when I first start it... but then after about 5 minutes of driving or 10 minutes at idle the loudness subsides. I am not a mechanic but the only thing I could think of is possibly a loose piece in the exhaust system that when it is cold allows escaping exhaust?? But when warmed up as the heat travels through it expands the metal and the gap is closed???

Seems a bit far-fetched but I can't think of anything else.

[Benzman]

Actually your exhaust sound troubleshooting seems spot on.
I'd check all of the bolted connections in the exhaust first.

Normal Idle is more like 800RPMs rather that 500.

[jeremywitt]

so what could be causing the low RPM idle??

[Benzman]

Possibly a vacuum leak.
Are there any other symptoms?