Been having this problem for a couple months where it would hesitate to to go into gear when I put it in any forward gear from park or nuetral. Now it seems to have gotten worse, the torque converter wont lock up at all it seems. Lets say I have the gear selector in second gear and Im running about 70mph at 4800 RPM~. When I let off of the accelerator (no i did not hit the brake), the engine RPM will drop to idle as I continue to coast at 70mph. When I give it some gas, it will just free rev until I get back up to the RPM that matches the speed I am going which in this example would be roughly 4800 RPM~. It will do thas in any selected gear, at any speed at any RPM, at any tranny temp and fluid level is fine. I did pull a code P0706 Transmission Range Sensor Circuit Range/Performance, shortly after it started to do this. I have a Yank TT 3000 torque converter. Other than that, the transmission is still shifting nice and firm as always.
-Thanks in Advance

 

My be the range selector switch no seeing the proper gear and the e pcm getting confused.

Also could be a pressure problem -lock up works off fluid pressure.
TCC Solenoid maybe plugged?Usually sets code though.
Do you have a scanner to check data?
A scan would help a lot.

 

Is it throwing a missfire?If it throws a P0300 then the converter will not lockup.

 

no missfire codes, I dont think I ever had a crank relearn done when I swapped engines and PCM, so I dont know if it is capable of detecting missfires, should I unplug a sparkplug and find out?

 

The rpm drop while holding it in 2nd and letting off the gas is what gets me.

 

No Do Not do that-you could burn out a coil or take a chance of a spike to the PCM.
Not counting the 100k thru your body