[Jackpine]

What year is your truck? Based on your mileage, I don't think you have plug wires! And, if it's a late model year truck, your plugs are supposed to be good to 100K. Some people have advocated changing them earlier, to avoid plug breakage, but that's all anecdotal.

My idle is steady and in the neighborhood of 600 rpm. I've never looked at that value on the Gryphon though, because it doesn't interest me - I just read it off the dashboard tach.

So, why is your idle wandering? I can only tell you an experience of mine. When I first got my Edge (now converted to a Gryphon) I tried advancing the spark - I think no more than 0.25 degrees. I got the same symptoms you have - a "strolling" idle. I moved the spark back to zero and all was well.

You might try retarding the spark about 0.025 from the setting you have it on.

But, before you do this, what Level are you programmed for with 93 octane gas and a programmer? Using the canned tunes, you SHOULD be able to advance the spark 1 degree in a Level 3 tune. Have you advanced it more than this? Did you advance it at all?

I'm asking questions because we need more information.

(As often the case, Bill beat me to this! - Stalling? Fuel filter? Danged if I know). Bill has posted a good bit of information on the PHP website in the FAQs about idle problems caused by a dirty throttle body. Pull the air cleaner box off and have a look.

- Jack