Finally went to test drive a new F-150 and was very disappointed. I want a 4X4 S-cab but the only 4X4 they had was a King Ranch with a dead battery and about 2 gallons of gas. After them jumping it, I took it for a ride and it felt severely underpowered. The DIC said 20 miles til empty so I know it didn't have much fuel. I was afraid to turn onto the somewhat busy 4 lane hwy next to the dealer so I just kept it on a couple of back roads. Does the truck's computer do something when it drops below a certain level of fuel? The the computer need time to 'adjust' after a dead battery and jumpstart? Is the truck just really underpowered and the heavy KR didn't help any?

 

Any time you have a dead battery or you disconnect it, the PCM has to reprogram itself. While this is happening, the engine runs on a base program that is installed at the factory. It's like a Windows operating system on your computer. The base program is always there, but all the updates you get change the program and make it more efficient. If something should happen, you can still run the computer on the base program. Unless, of coarse, that gets damaged as well.

 

A couple points:

As far as "underpowered" goes, remember, you drove the heaviest configuration F150 you can get. Somewhere north of 5500 lbs I think.

And as Tbird pointed out, the fuel trim and trans tables may be kinda funky because of the lack of battery power. Sometimes, you've gotta run them down the road for a few miles for the PCM to go into adaptive strategy and relearn fuel trim and trans tables so it can get it's bearings again.

 

Jumping out of a Lightning and jumping into one of these you will be disappointed.

 

I was gonna mention that too.

 

Yeah, I figured the PCM might need some time. I'm going to give them another chance. I will make sure to drive a Scab 4X4 which is what I want. BTW, I'm looking to replace my 180 HP '95 Chevy Ext. cab so I'm not a stranger to a 'truck'. Never wanted to compare it to my Lightning.