Good day,
I have a 1985 740 GLE with an M46 manual transmission with overdrive.
Overdrive acts flakey.
At normal to high temps, the overdrive can be engaged shortly after hitting the road. The warme it is, the quicker it engages.
At low temps, it takes quite a while but it does eventually engage.
I have eliminated the switch on the gear selector (shifter).
I have opened up the relay and cleaned the coil contacts.
I have checked the terminations at the solenoid.
I addition, if I move the gear selector to the left a bit, the overdrive will disengage leading me to believe that there are 2 problems; one with the 4th gear switch and something somewhere else.
I see on the schematic, that the EGR solenoid is in the same circuit but I figure that it's just drawing power from the same place as the relay circuit.
Where exactly is the 4th gear switch? Under the console? Can it be adjusted? Can I reach it without pulling the console?
I have pulled the top cover of the console off, but never the shifter boot.
Any ideas on the overall problem?
I don't really want to "diagnose by replacement" the solenoid as it is pricey.
Could this be a problem with the transmission oil? Drain and change?
TIA
regards
jimB
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