Force Motor current (not typical question)

[starks]

car is a 98 buick regal gs.

I'm having an issue at idle where the car wont move (once warmed fully) unless i give it some gas then it finally "catches" and then moves. it seems its not getting any fluid unless the pump goes faster. im going to switch the filter tomorrow to see if it was partially plugged but it has come to my attention that i may have a leaky input clutch piston, and by revving the car the increased pump pressure is overcomming the leak.

what im wondering is if i can increase transmission pressure, but not at the shifts, all the time. im wondering if the force motor current table can do this. it appears not as the table is under "shift properties" but i figured id ask.

[gman4dx266]

Yes, lowering the FMC table will lower the 'big picture' line pressure. Right now my trans in my truck is on its absolute LAST leg (no 3rd gear and no reverse at all and 4th gear slips pretty bad; horrible whine noise in neutral & park) and I have my force motor current table set to ZERO (LOL) with it stock it will pretty much do nothing.

Be aware the more line pressure in the trans, the more you have in the torque converter as well, since its 'plumbed' into the ATF as well.

[n0dih]

If fluid/filter are ok and zero'd out FM table, you have a mech problem and most likely that leads to a lunched trans. Broken accumlulators often allow fluid leak to the pan and is like slipping a clutch on a stick, only the clutch material is fractions of a mm thick.... it doesn't last.

Yes, lowering the FMC table will lower the 'big picture' line pressure. Right now my trans in my truck is on its absolute LAST leg (no 3rd gear and no reverse at all and 4th gear slips pretty bad; horrible whine noise in neutral & park) and I have my force motor current table set to ZERO (LOL) with it stock it will pretty much do nothing.

Be aware the more line pressure in the trans, the more you have in the torque converter as well, since its 'plumbed' into the ATF as well.

[L67s/c]

starks did you ever get an actual solution to this prob through tuning? i have the same issue and id like to fix it also.

[n0dih]

I was looking at something today, look at the Min/Max % TCC Duty Cycle vs line pressure vs trans temp table. If you rail the Main line pressure tables, you will push the PWM TCC lock to slip more. So you may need to pull some slip out of the min/max tables. In other words railing one may complicate another.