Colder Temperature Better performance

[Danson]

hey everyone,
i have the sohc motor in my explorer it has been replaced and has had a complete tune up but the problem is when it is colder out it runs and drives and has great performance but when it warms up, you notice the difference in power, especially on a really hot day, does anyone know what this could be??

 

[Dan Whitaker]

Cooler air creates a denser charge (air/fuel ratio) meaning you get better combustion.

 

[Electrohacker]

also elevation plays a role as does humidity

you want cool dry air. here in MI i find 45F is just about right

 

[Danson]

should it be that noticable it was 38 C here today and the thing did not want to go, it runs perfect until you really hit the gas and i can only get aot of power once i hit about 4000 rpms, if i floor it off the bat, it slowly moves out as if i was giving it 3% throttle, could it be fuel injectors??