hesitation during acceleration?

So when i changed my plugs a while ago they where a little on the whiter side like the motor was running lean. I figured it was normal since its an EFI truck (2.7l). It always kinda bothered me, but now i am noticing it more an is getting pregressively worse. When the truck is warmed up not so much as when its cold, if i punch the pedal or even just slightly aggressive with it the truck will kind of bubble and stumble before catching up and reving out. My truck is a manual tranny and this happens without letting the clutch out (not under load) but happens under load as well. I have no idea other than maybe a fuel problem? fuel pump? idk it only happens on the low range and around highway speeds my pick up is terrible!!! i have to be in 4th gear around 4000-5000 RPM for any kinde of "passing speed" on the highway.

I dont know any ideas??

Thanks
Wolfgang

 

Fuel filter stock? Seafoam, clean throttle body, maf sensor? All of those will make a big improvement on performance. If your concerned about it running lean you can do a fuel pressure check. If its a fuel problem check the fuel pressure first before you go out and buying parts.

 

Fuel filter is stock, 107,000 miles so that probably needs a replacing. where is it? i have seafoamed and cleaned the throttle body as well as MAF all at 100,000 miles. how do i check fuel pressure?

EDIT:

found this for replacing the fuel filter:

http://www.tacomaworld.com/forum/1st-gen-tacomas/127947-fuel-filter.html

 

i also plan to replace the PCV vavle

 

Yea that is a good idea to replace them every so often, I need to replace mine and my fuel filter also. And Im not 100% sure on how to check the fuel pressure on these trucks, but google and youtube explain it well on other vehicles.