99 FG odd increase in power

kerry

Expedition Leader
Owned it 11 years so I'm pretty familiar it's feel. Drove from Denver to Valentine NE last weekend. Felt to me like I had about a 10% increase in power. Held it's speed much better on the hills. Didn't have to shift down at all going through the Sand Hills. I might have thought I was just imagining things but I have a vacuum gauge which pulls down and locks between the filter and the turbo in the intake system. It's been there about 6 years and it initially pulled down about 1/4" inch and has stayed there since. I glanced over to see it at camp and noticed it had sucked down an additional 1/4" or so, telling me the turbo was sucking more air (or the filter is dirty). The last trip prior to last weekend the orange service engine light came on when I parked and restarted at about 11500 ft. It went out shortly thereafter. Could that have initiated some kind of computer reset? I don't know how the computer controls the injection. I wonder if a reset did something to the electronic throttle mechanism giving it more fuel. More fuel, hotter burn, more expansion of gases, faster turbo, more suction in intake?? It's very odd and I don't think it's my imagination even though I don't have before and after dynamometer readings. Apart from the lack of downshifting, I also felt as though I didn't have to press as far down on the accelerator to get the same response as I used to get when holding it to the floor. I'm not complaining. The truck is much more pleasant to drive in its current condition. :)
 
Last edited:

yabanja

Explorer
Do you use any diesel additives? I find Cetane booster helps significantly with power at least here in the USA.
 

kerry

Expedition Leader
It’s my understanding that the USA 1999FG has very little computer control of the injection system. I read that it basically controlled the idle system and the engine would run without the computer system operating. I’ve never confirmed this personally but if it’s true a tune won’t accomplish much.
 

Forum statistics

Threads
185,891
Messages
2,879,276
Members
225,450
Latest member
Rinzlerz
Top