Getting Cooler out, truck is running much better...Why?

[BillZ260]

I understand the cool dense air allows more for higher compression which may be explanation enough, but I want to make sure I completely understand.

 

Here's my issue, basicaly my 94 explorer w/ 140K miles is starting to show it's age. It's been way down on power, especially over 3K RPM, detonation is aweful with premium gass, and check engine light is on / off all the time due to rich / lean signals.

 

This morning, a big cold front came in, was in the upper 40's and raining. My truck was running like it used to all the time, pulled hard, even past 3K, NO detonation at full throttle on the hwy, it just ran right.

 

So my question is: "Is it simply the cool air in the cylinders that is helping my truck along, or is the air temp effecting some other components, such as the oxegen sensor or MAF or something along those lines?" I think that there must be alot of carbon build up in the cylinders, which has raised the compression enough to make it run poorly when warm out, but ok when the air is cool.

 

Any insight is appretiated. If my wife gets accepted in this program she's wanting in, this is going to have to stay my daily driver for a bit longer. I'd like to do what I can to keep it in shape.

 

I guess if I had to I could share my A/C with the intake inlet

 

Thanks.

[Thumper]

One thing it might be is if your Intake temp sensor, or your coolant temp sender is broken or worn and they are reading your car to be cooler than it is, your ecu will inject more fuel. And when its hot out it is too much fuel and your car runs bad. But when it gets cold out and more air (because its denser) gets into your engine the afr's are closer to where they should be you car runs better. Just one theory. Another one is...

[BillZ260]

Thanks Thumper, that's the type of info I was looking for. I'll start seeing what I can come up w/ on some of the Explorer forums as well.