runs better when cold

[Corik]

Hi guys I was noticing lately that my Explorer runs stronger when its cold outside. Like today I was driving to school like normal, and I parked and left it there all day. Got back after classes and Drove out ( drives like expected) got some lunch/dinner before my night class and parked again for about 4 1/2 hours. When I get back its cool outside probably 50s.

I start up the truck and its feels like more power. I was messing around and floored it since theres no one else on the road and it accelerated better than usual.

I just want some ideas on why this might happen. And I'm pretty sure it does it even if I didn't drive earlier that day

 

[mr cribb]

Cold air is denser and more can be crammed into the cylinders. It also leans out the fuel mixture...

or read this: http://www.fullsizebronco.com/forum/showthread.php?t=135740

 

[Corik]

palm to face* cant believe I forgot about the whole idea of cold air intake. I don't have it though, mine is stock.

thanks!

 

[FIND]

Your factory air intake draws cool air in from below the engine. There is not anything you can really do to improve it, when it is warm, you are going to have a little less power than when it is cool.

 

[malohnes]

My truck has the same issue, no pinging until it warms up. I have a sneaky suspicion that it is related to timing. I have made a RAM Air intake on my truck and here in Alaska, it is never warm enough to really cause issues with intake air temps being too warm.

I have not found a fix yet, but I am narrowing things down. do have some worn valve train components, so until I replace them, most of my troubleshooting is done. I have cleaned and replaced all the usual stuff on my nearly original engine, except the upgrades mentioned in my signature.

Let us know what you discover.

 

[Sparky94]

Mine is like that too. It is better in every way, even with mpg its better. I drove 75 miles w/o stopping at an average speed of 60mph, an outside temp of 60-65 degrees, with two passengers, and managed to get 24mpg. It also passed anything like it was nobody's business.