Transmission Drag

[4x4 AG]

Some of you may remember my thread on the Low Idle Issue I was chasing.

Cliff Notes:
- Idle drops low when sitting in Drive at a stop light.
-Changed or checked: IAC, Throttle Body, TPS, CPS, Smoked engine and EVAP, Pressure checked Exhaust, new Cats and O2 sensors.
-Even asked ChatGPT to help me, which it was pretty good actually.

So now, what I am wondering, is what someone mentioned initially,

IS THERE A DRAG ON THE ENGINE BY THE TORQUE CONVERTER?

How could I check this? I have basic tools and knowledge. Am YouTube certified as a mechanic. So please follow the K.I.S.S. method for me.

Thank you Brain Trust.

 

[speeding_infraction]

IS THERE A DRAG ON THE ENGINE BY THE TORQUE CONVERTER?

Yes. You will notice that if you shift into park or neutral it will idle normally if that is really your problem. What diag work have you done on it?

 

[Wildman]

Have you tried setting the parking brake & taking your foot off the brake pedal? If you had a vacuum leak in the brake booster this could cause your issue...