Issue with 1st gear, extremely slow throttle reponse.

2006 4runner SRS 4wd w/ 101k
I looked up several forums trying to see if anyone had the same issue.
I see one is having the same issue as mine but what else could that be?
Issues with acceleration | Toyota 4Runner Forum [4Runners.com]
For me, I have 0 codes.

Normally I always allow 2-3 minutes to heat up the engine. After that, 50/50 it would launch extremely slow (about 3-4 seconds) on 1st gear then revving up to 3-4k.

If the temperature is cold or hot it does not matter. Still having the issues. 50/50. meaning sometimes it works fine, sometimes not.

What I've done-
Changed oil filter/air filter.
Used Premium gas 93 for a week.
New Spark plugs.
Yesterday, I cleaned TB.

Update: Finally got a code - P2714 and P2714 P.
P2714 Pressure Control Solenoid D Performance Or Stuck Off (obd-codes.com)

That same day, I removed the code, didn't touch it.
Next day, its running perfectly.
I'm thinking I need new transmission fluid.

 

Start with changing the trans fluid, yes. But you might have failed solenoids in the transmission, per that code. This is not an engine related issue, this is strictly to do with the transmission now.

 

Yes, that is a transmission/solenoid issue. Ill get back to you once the fluid is changed.

 

Changed the ATF fluid. Didn't see any sentiments but it seems like the fluid was a little low. I only counted 3 quarts when it should have been 3.2. We'll see if anything changes.