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722.9 transmission error P089300 Hydraulic fault in transmission
I had a case of transmission "dropping to neutral" (for the lack of better description) under heavy acceleration when the car failed to upshift. No errors on dash, D/S/S+ shown on selector, engine revs, but no torque applied to the wheels. After coasting to a stop and re-staring the car went to D as normal and drove. During further testing I noticed that 3-4 shift under load always takes "very long time", feels like its 2-3 times slower than most other upshifts, close to a full second perhaps.
I found an interesting bit in transmission adaptations values, 3-4 shift has 15.5/10/10.5 for times while most other shifts are way lower:
Any opinions on what might be going on and what to make of adaptation values above ? What should I try from xentry/software/adaptation, as opposed to hardware?
This happened to a bunch of us after our tcu tuned and we aggressively tested with dragy etc. exact same thing - goes to neutral and no codes or lights, restart and car is fine. More often would happen if I was brake loading to above 2000rpms then launching.
it's some fail safe I think. Also happens if I hit a bump while aggressively accelerating and the wheels spun on recoil from the bump.
Thank you for the reply, knowing it's somewhat common is some relief
I'm not TCU tuned, but did experience the issue while accelerating over bumps, or rather indentations in the road.
@PeterUbers How often do you change transmission oil while tuned ?
Thank you for the reply, knowing it's somewhat common is some relief
I'm not TCU tuned, but did experience the issue while accelerating over bumps, or rather indentations in the road.
@PeterUbers How often do you change transmission oil while tuned ?
yeah nothing to worry about.
just as per routine maintenance requirements. A lot of that reasoning is that I don't beat on the car much so it's not really worth me being more aggressive I don't think. If I drove it daily and was more aggressive I would halve the interval to increase the frequency of trans fluid changes
inconsistency is what's bothering me, I can't reproduce it at will. plan on doing the transmission oil change, perhaps something will be clear after dropping that pan
inconsistency is what's bothering me, I can't reproduce it at will. plan on doing the transmission oil change, perhaps something will be clear after dropping that pan
If you get this over routine bumps in the road then it's abnormal. A bunch of us would do a 1/2 mile event and one lane had a dip and every 63 and some other cars would have trans faults as we hauled a$$ from zero to 150's mph....
not routine bumps. it was a few longer and deeper indentations in a row where whole suspension compresses and then relaxes to the feeling of taking off the road gently. hard to explain
I did trans oil/filter service (no notable debris according to shop), reset shift adaptations and went on a 1,400 mostly highway miles road trip, most of it in S (not S+)
So far no shift issues, other than expected rough non-adapted shifts. Adaptations seem to be trending to the pre-reset values, 3-4 stands out again.
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