Fast Idle from nowhere!

I have a 2001 Taco, 106,xxx miles. I was on vacation for 2 weeks so the truck sat. Since I've been back, it has been constantly idleing at 1200-1300 rpm's, even after driving for an hour or so. I'm not sure where to start to diagnose the problem. FYI, I haven't done the timing belt yet, due to get that done in a month or so, could that be related?

 

No one?

 

If it idles high and rough, I'd say you might have a vacuum leak. Or the idle air control pintle got gunked up and jammed open. I would also try cleaning off the mass airflow sensor. Beyond this, having a scan tool would be helpful.

And unless you jumped a tooth on one of the camshafts, which you would definitely notice, I doubt an old timing belt would do this.

 

Thanks for the reply. It has since gotten better on its own, I'm not sure if it was just bad gas or what. The idle still surges a little, so I'm planning on getting some seafoam when I have some time.