Alright.. I bought my 1999 F150 4x4 about 3 weeks ago.

Suddenly in the past 2 days I've been having this weird sensation that I've dropped some power in the engine for some reason. I can't explain it... it just FEELS like it doesn't pick up and go ever so slightly as much as it did a week or more ago.

Is it all in my head? UGH. I hate this feeling.... I'm almost certainly imagining it.

 

Possibly due to heat???

 

Maybe you've done used up all the racin' fuel the dealer put in.

 

wouldn't by any chance of just started using your A/C?

 

Let's see if I can capture answers for all three responses in one message:

It's been really hot all three of the past weeks. However... it might have been hotter this week than the previous two.

If they DID put some racing fuel in there... I NEED some of that stuff!

Been using the AC all along.

 

Well since I live in TN just one state to the north of you in the summer the truck seems to lose a little of its get up and go due to the heat and very humid air as well as using the AC.

 

Try going out for a ride anytime after about 10:00 at night after it has started to cool down. If your power seems right at night in the cooler temperatures you can assume heat is the problem your expierencing. Between having the AC on max and the heat during the day it's pretty suprising how much of a difference there is in power on my truck between 5:00 in the day and 10:00 at night. I believe you loose between 12 and 15 horsepower running your AC, and I wouldn't be suprised if you lost atleast another 10-15 horsepower in the extreme heat. With between 25-30 horsepower lost together, you should notice a difference!