power surge?

[SoWoCo]

I have a 1987 F-250 with the 6.9.... sometimes when I am accelerating full throttle in 3rd and 4th gear (t-19) I get a 2-3 second power surge randomly (not when I punch it, and not at the top end) I was wondering what would cause this and I if there was some way I could experience that amount of giddy-up all the time

 

[plywood]

Ever put your foot on the throttle and nothing happened for whatever reason (say out of fuel) and your head rocks forward because you expect acceleration.

I think it's the equal and opposite thing here, I don't think you're getting any more power than your truck already has, it just "feels" like more power.

In any case it's usually either air intrusion which would have to be prior to the lift pump, or it's an IP problem, either in the governor or the advance piston.

 

[TBigLug]

What's your fuel level?

If your sucking air you'll get that seat of the pants boost feel. Or if your advance solenoid sticks open it'll do the same thing (ask me how I know). Next time it does it look out your mirror at the exhaust tip and see if it's smoking excessively. If so, probably advance problem. Either solenoid or worn out pump.

 

[Mr.Diesel]

This is very interesting to me...as I get the same and have been wondering why. I believe mine is getting air in the line. It seems to only happen when I get below 1/4 tank, and it happens on either the front or the rear. And usually it will stall shortly there after, taking a fair amount of cranking/throttle to re-start. But MAN it runs good for that 2 seconds!

 

[OLDBULL8]

Take a baking pan and fill it quarter full with water, now swing it to the left. Where did the water go? Ah ha, same with a fuel tank. Bottom of pickup still there?

 

[plywood]

Not only that, but the pickup is probably broke off too.

 

[icanfixall]

Most of these trucks loose the fuel pickup and we run out of fuel around 1/4 tank. You can easily fix the front tank without dropping it. Get under the truck and find the top middle of the tank. There will be an electrical plug and two fuel lines. Remove all. Then use a chiesl or hammer and screwdriver to knock loose the retaining ring that holds the unit in the tank. Pull it out. Now add about 3 inches of diesel rated fuel hose to the end of the pickup. Done that easy. Cut slots in the end of the hose so it doesn't suck down to the bottom of the tank. Be careful reinstalling the cover. There is an alingment pin and it needs to be matched to the cover. The back tank will require the bed removal or dropping the tank... Either way its a tuff one man job...