Low end bog/lack of power

[Brent_G]

In my f150 I noticed since I have started driving it again it has a pretty bad bog. When it is cold and you pull out anything under half throttle it slowly takes off and it sounds like the engine is laboring, then after a few seconds it comes out of it and pulls normal. Once hot the bog is gone but it has no power really under 2k rpms or half throttle or so. Going down the highway at 55/1400 rpm you can gradually give it more gas and it won't speed up until it kicks out of OD.

No codes and still plenty of mid and top end power. Didn't notice this in July when I was pulling with it either. Anybody have an idea what it could be?

 

[eljefino]

lazy o2 sensor or junk coated MAF sensor more'n likely.

 

[Brent_G]

I'm gonna check the MAF now. Would a lazy O2 effect it when cold? Since it is in open loop the computer should be ignoring them. But I spose in open loop, i bet the MAF plays a large part in fuel trims, I think?

 

[crw]

This is probably not it, but around here we swear by a product called HEET. It's mostly methanol. Really cheap, and it is claimed to remove water in fuel. I think it helps even more when ethanol fuel is part of the equation.

In my Mini, I had a bog just like you described. The car was "new to me"...

I looked at the air filter. It was absolutely full, so I replaced it and found a slight gain in performance, but still had the bog...

I checked the spark plugs. They were completely gone. I replaced them and noticed an improvement during normal driving, but the bog at idle was still there.

I ran a treatment of Techron. Didn't do much.

Then finally I put some HEET in the tank. Wow, the bog is gone!

So it may be worth a try for less than $2.

 

[2oldtommy]

I assume you have tried Techron or Regane thru the fuel system. If not, that would be the best starting point IMO. FWIW

Oldtommy

 

[eljefino]

All I can say is my 94 B4000 (ford ranger) had dual heated o2s that were lazy and raised a ruckus after about a 45 second warmup. Ford seems to really pay attention to that sensor.

You can unplug 'em and see if open loop is any better. If your MAF is toast, it could be worse!

 

[Brent_G]

I cleaned the MAF as best I could and it seemed to help. I'm gonna grab a new one and get some new o2s and they should be done anyway.