Hello everyone. I am new to this board and hope I may get some advice. I have searched throughout the forum and there are many similar posts, with good results. I have tried everything to get rid of this problem. My truck likes to hestitate when I accelerate. Only once in awhile. Not consistant at all. Also when I barely give it throttle. Here is a list of evrything I have done.

1. Seafoam
2. Plugs & wires. (Not the coil packs)
3. Throttle Position Sensor
4. MAF cleaning. Twice to make sure.
5. Throttle Body cleaning. (Removed when done)
6. Fuel Filter
7. O2 and A/F sensors.
8. Air Filter (k&n)

None of these have helped with the issue. My only thought now is injectors. Oh it is a 3.4 V6 auto also. I am at a loss now. Oh and all these parts came from Advanced, nothing from Toyota. Not sure if this would matter.

 

Hey Kutch
I have the same problem & have tried most of the same things, also did fuel pump. Used BG44k multiple times, but it didn't help. Actually just finish water pump and timing belt last month (water pump was weeping). Like you, I'm not sure where to go, maybe injectors, valves or muffler? Replace the CAT last year.
If you made any progress please let me know. If not, maybe we can work together to solve?

 

I'd look for a crack in one of the vacuum hoses I just got done swapping my motor and noticed some fine cracking in some hoses so I replaced them

 

Follow-up just in case someone reads this post with a similar problem.

My problem ended up being the TPS. Replaced the TPS with a NAPA one last year when I was having problems with emissions. The resistance readings on the NAPA TPS were within the FSM "OK" ranges, yet much higher than the original TPS which luckily I still had. My daughter recently bought a 2000 4Runner & I decided to check the resistance readings on hers. Sure enough, the readings were low like my original TPS. Put my original TPS on & the problem went away. I'm slowly finding out that it's just better to get original OEM parts on-line even if you have to pay extra.

 

Yotawitz

This was exactly the problem. I ended up taking it in to the dealer so they could troubleshoot it. They said bad TPS. I was pretty mad that I wasted all the time and $$$$ on it. Lessoned learned. OEM for now on.