CLK-Class (W208) 1998-2002: CLK 200, CLK 230K, CLK 320, CLK 430 [Coupes & Cabriolets]

722.6 tranny help

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Old Aug 7, 2012 | 12:02 AM
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clk320
722.6 tranny help

Thanks in advance for any help.... just bought and restored.

Vehicle:
2002 CLK320 with Autostick. 50,000 miles. Ex-flood.

Symptoms:
P0730 incorrect gear ratio (I think it thinks it should be in 4th but it isnt)
All gears work fine except for 4th. When car shifts to fourth gear for half a second it feels like it will shift and work, then goes into what feels like neutral and free revs. If I slow down so that the car needs to shift into 3rd or lower, the car will then shift and drive as normal in the lower gears. Autostick will let me shift through to 3rd but will act the same as above when shifted to 4th.
Tranny ran fine post flood after I serviced it. The symptoms happened about 30 miles later: when I went to get it inspected, the motor heated up to 120 degrees as the fan relay needs to be sorted. When I left the inspection station I could smell tranny fluid and the problem started.



Previous Knowledge and Actions
Tested pinouts to 1-2 and 3-4 solenoids. Both show 4.0 ohms vs 2.5-5 as acceptable. So seems Ok.
Tranny Fluid found in connector to transmission. Replacing with new pilot bushing, light wick towards TCU, however, TCU clean.
No metal in pan, slight dusting of black swarf. (I assume friction plate material)
I have taken the valve body and conductor plate out and am inspecting.
Replaced filter, fluid, replaced shifter with used shift lever, post flood. The TCU was dry and clean as it hangs upside down and fluid was held out by trapped air.

Questions and Logic:
Can fluid in the connector to tranny cause 4th gear to not shift? I know that technically tranny fluid is an insulator and not a conductor, unless of course enough graphite or material is in the fluid.

Possible 4th gear valve?

Shift lever was used when installed....could this be the suspect if only 4th gear is not engaging?

Could the conductor plate be shorted?

Again, all works well except 4th. The car tries to shift to fourth, yet it doesnt engage and free revs.

Thanks for any leads or feedback experience
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