Surging or Lunging while towing at low speed

So my issue is no matter what the cargo is if I am trying to tow I get a Surging or lunging while towing at low speed. I just changed out valve covers, spark plugs, valve gaskets, wires, coils, mass airflow I have a cold air on it. no codes are being thrown there’s no issues I can tell with my live mode on my OBD2 scanner there’s plenty of fluids in the rear end and in the transmission everything has been lubed I can’t find anything on it online so I’m coming to y’all

 

If you put the stock intake back on, does the problem go away?

Cold Air Intakes are the bane of cars running correctly.

 

No. This was an issue before I did any of the listed upgrades/ services. It’ll go away as I speed up but it’s really bad below 25mph. It feels like there’s a flat tire on whatever I’m towing

 

Throttle position sensor can causing a jerking type motion at certain speeds.

 

Only while towing? It’s about the only thing I haven’t changed

 

I'm just throwing ideas out there because I had a similar type of problem. I wouldn't want you to just throw Parts at your 4Runner but for $40 and five minutes of your time, it might be worth it. I would replace it just because of your high mileage.

 

Just an idea/what if. At those lower speeds and towing in D mode, it could be that the trans is hunting for the right gear. And even the slightest change in pedal pressure could be making the trans shift up or down.
Do you see or notice a change in engine RPM?

 

I’ve tried it in all drive positions/ gears and useing both od button and ect power. I’ll look into the tps and let ya know. Open to all ideas tho.