Hot weather= slower idle?

[MMeier]

Anyone else's truck seem to experience a slower idle speed when the ambient temp gets above say... . 95-`100* ?

 

[Makaio]

Yeah, Mark, happens all the time. My truck runs its best during the cooler Hawaiian nights. The warmer air is not as dense.



Aloha,

Matt

 

[dpuckett]

I have noticed the same thing through the years, and there seems to be no pattern. It normally happens when I am driving a long time on the highway, and the idle seems a little lower than when I started. I figured the fuel expands, reducing the density, and thus the power production per cubic millimeter pumped. With the pump set to idle with, say, 90deg fuel (relatively cool, all things considered), it can idle lower with 150deg fuel.



And then I've had other trucks idle the same speed no matter what temperature anything is. Weird. Makes me think the slower hot idle could be a sign of beginning pump weakness (?)



Daniel

 

[DanaLittle]

My truck idles lower in the hotter weather too. It also smokes alot more.

 

[MMeier]

My truck idles lower in the hotter weather too. It also smokes alot more.

Yep, forgot to mention the more smoke part, must be normal then, and my PODs I suppose don't help in any regard either.

 

[Greenleaf]

In a word. YES.



Trun on the heat (ambient temps) turn on the A/C and put the engine in "D" and I see about 550 RMP's. When at a stop light, the smoke (idle haze) from the stacks, is a real sight.



Now I mix 2-cycle oil in my fuel and the idle smoke is :--)