- Location
- Southern Maryland
I have noticed that the '94 AW4 I just swapped into my '91 has a shift flare from 3rd to 4th, where the engine rev up and the tranny shifts kind of hard. I hooked up my mechanics scanner to the TCU diagnostics port and found some interesting things. Specifically, when the '91 TCU "Comfort" mode is selected, the shift pattern is as follows:
1st
2nd
3rd
3rd w/ torque lockup
4th w/ torque lockup
The lockup solenoid does not disengage before shifting to 4th, which produces a hard studder since the tranny is getting all of the crank power
Conversely, when the "Power" mode is selected, the shift pattern is as follows:
1st
2nd
3rd
3rd w/ torque lockup
4th
The TCU does not command the lockup solenoid to engage in overdrive when Power mode is active
This all seems a bit weird to me. Does anybody know if this correct behavior?
1st
2nd
3rd
3rd w/ torque lockup
4th w/ torque lockup
The lockup solenoid does not disengage before shifting to 4th, which produces a hard studder since the tranny is getting all of the crank power
Conversely, when the "Power" mode is selected, the shift pattern is as follows:
1st
2nd
3rd
3rd w/ torque lockup
4th
The TCU does not command the lockup solenoid to engage in overdrive when Power mode is active
This all seems a bit weird to me. Does anybody know if this correct behavior?