How steady should the idle be?

I have an 05 Silverwing. It starts quickly and runs great.

The only issue is that the idle appears to be a little unsteady. I believe that the spec is 1300-1400 rpm but it drifts back and fourth around 1300 with the low about 1100 and the high around 1500.

Is that condition normal or could something be going on?

Thanks in advance for advice on this.

Sounds normal to me, as long as it runs good I wouldn't worry.

When warm, mines idles around the 1200 mark. pretty steady.

Mine once warm is steady at 1,200rmps...

Magoo

Mine runs very steady - of course it runs higher when it's cold than hot, but steady in both cases. I don't get any surging at idle. In fact, my 2012 Chevy pickup - with all the advanced electronics and computers - has a lot more unsteadiness than the Silverwing, which stays exactly where it's set to idle. Actual idle numbers aren't too useful to compare, but steadiness is. It should be steady.

Some possible causes: leaking fuel regulator, dirty injectors, dirty air filter, old/bad gas, clogged fuel filter (this is not a trivial check so I'd wait until I ruled out other things), idle air mixture screws misadjusted, intake air (or vacuum) leak, etc.

jmaslak wrote:

Some possible causes: idle air mixture screws misadjusted,

I'm sure you mean throttle plate synchronization screws.
Mixture screws are found on carburetors.

My engine idles at slightly different speeds depending on both ambient and engine temps. On cold start, it's around 1600 rpm. As soon as closed loop operation starts, at 2 bars on the temp gauge, idle drops to 1350. After a hot soak restart, idle is lower at 1200. After an extended high speed run, idle sits at 1400. I have synched the throttle plates using the method in the service manual. I prefer my idle on the higher side of factory specs, thus the 1350.

Mine idles very steady with no fluctuations.

Mine fluctuates a little when the engine is cold but it's fine when warm.