TCC code P0741 - need advice

[mandkole]

yes, in those events, it describes the issue that ive been concerned about the whole time. The converter had been commanded locked 100% (my tc lock light has been on). I then fed a little throttle and it tried to unlock then relocked.

In the reading Ive been doing (especially from Sonnax), it appears that the TCC valve in the pump could be the issue. Is this what you are referring to below? All of the signs are there; increased delay to lockup with under light throttle, erratic unlock after lock, elevated fluid temps (compared to normal) , etc.

 

[Mark Kovalsky]

Yes, that's very likely that it is the torque converter control valve, located in the pump body.

 

[mandkole]

^^ yup, this issue and the past issues are adding up. IMO, the pump has had issues since Ive owned it but I didn't know it.

-first observation at purchase was the TC load (more than what I ever thought was normal) on the motor in gear with brake on
-few months later, next issue was the sudden converter drifting on and killing motor when put into reverse
-the drifting effect stopped but now the lock/unlock with significant slip rpm

According to my trans shop buddy, the TC slip rpm should be almost zero. Theory is that likely the historic pump issues (cross leak, etc) have not been managing the clutch operation all along and wearing the clutch plates. Makes sense that now the TC will not stall the motor when grounded in gear with brake on.

The trans needs to come out for a TC, pump and review. Ugh...

Mark, thanks again for the comments!

 

[Jake]

Subd.... May be in the same boat..... P0741 and the over heat code