R320 surging at low throttle
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R320 surging at low throttle
I have a 2007 r320 with 230k Miles. It was stuck in limp model for the 2 whole years the last owner possessed it (26,000 miles without a Regen 🤣 it has been deleted, new transfer case chain, oil cooler seals, turbo actuator, egr bypassed and blocked off, rear main seal, oil filter housing seals etc etc.
No stored codes.
The issue: when cruising between 30 and 55ish mph, light throttle; you can feel the car surging via your seat and the tachometer fluctuating about 180ish rpm. On the way home this evening I ran some logs on the transmission torque converter slip speed and it appears this is my culprit. When I stand on it to give her the beans, I assume the line pressure goes up and it holds all the power with less than 9rpm of slip... But when you let off to maintain speed, it goes back to surging... Unless your doing 60 up to 110
Has anyone had this issue before? I'm hoping a fluid change and a new lockup solenoid will solve it. Really don't wanna pull the transmission again 🥴
Attached is a graph of the TC slip speed over a short time.
07 r320 TC slip speed over time causing a surging feeling
No stored codes.
The issue: when cruising between 30 and 55ish mph, light throttle; you can feel the car surging via your seat and the tachometer fluctuating about 180ish rpm. On the way home this evening I ran some logs on the transmission torque converter slip speed and it appears this is my culprit. When I stand on it to give her the beans, I assume the line pressure goes up and it holds all the power with less than 9rpm of slip... But when you let off to maintain speed, it goes back to surging... Unless your doing 60 up to 110
Has anyone had this issue before? I'm hoping a fluid change and a new lockup solenoid will solve it. Really don't wanna pull the transmission again 🥴
Attached is a graph of the TC slip speed over a short time.
07 r320 TC slip speed over time causing a surging feeling