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Yes but much reduced. I think it's more to do with holding the higher revs. It doesn't drop into neutral unless going very slow
L322 ZF8HP70 gearbox problem
- Thread starter kermit_rr
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I don't know if it's related but SDD is still not happy, complains the deployable side step isn't running.. well it's never had one!!
I also read somewhere about invalid ccf but can't remember where i saw that. It didn't say what was invalid
I also read somewhere about invalid ccf but can't remember where i saw that. It didn't say what was invalid
Then the torque converter is locking up OK, back to looking at speed and torque values - have you checked the output speed sensor is reading correctly?
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i havent, i'll plug SDD in tonight and have a look. presume its called something obvious
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What reading should i be looking for, how do i know if it's good or bad? And which speed sensor
Datatek
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As said, "output speed sensor". With live data and the car moving it should produce a signal but since I know feck all about the L322 diagnostics where it will appear and what it's called, I don't know.
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If you had clutch/torque slip you could have an input/output sensor correlation fault possibly? 
The speed sensor for the transmission output in rpm - not the wheel speed sensors or the composite road speed on CAN, an actual rpm value from the TCM, there is also a turbine speed sensor (Transmission input speed) also in the TCM, there are not that many PID's in the TCM so you should be able to identify them - you're looking for the readings to be plausible - i.e. output is >0rpm when the vehicle is being driven and smoothly increases/decreases, same goes for turbine speed but you don't need to be moving to read that one. I can't remember the correlation to engine rpm (it may be 1:1) but it'd be worth having that displayed along with the turbine speed to check for any anomalies in speed variation - also check in 'S'.
That would/should set a DTC, if the value is incorrect but still within the valid range, that'd give symptoms but no DTC.If you had clutch/torque slip you could have an input/output sensor correlation fault possibly?
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Very true, Clutch opening and shutting time limits.
There seems to be a trend of solenoid gauze blockages. Vw Audi has a gearbox setup that suffers from this type of issue.
There seems to be a trend of solenoid gauze blockages. Vw Audi has a gearbox setup that suffers from this type of issue.
Henry_b
Think outside, no box required.
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Have you had the adaptions reset?
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I didn't see a live data selection called output speed sensor but saw a few others.
Transmission output shaft speed was interesting, it was at zero apart from a spike when starting and a spike when stopping.
There was transfer box motion sensor voltage which went from low to high, the switch happened before i came to a stop
Transmission output shaft speed was interesting, it was at zero apart from a spike when starting and a spike when stopping.
There was transfer box motion sensor voltage which went from low to high, the switch happened before i came to a stop
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It was supposed to have been done by the guy who did the oil change
Henry_b
Think outside, no box required.
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8hp has a reputation for issues in the valvebody usually pressure leaks that can cause the trans to act erratically.
The priming valve in the valvebody losing fluid pressure is a favourite that can cause it to shift poorly.
The priming valve in the valvebody losing fluid pressure is a favourite that can cause it to shift poorly.
Datatek
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That does not sound right to me.
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In the higher gears, with high throttle inputs it seems fine, there would be greater leakage and bigger symptoms?
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That's what i thought
Datatek
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No signal to indicate that the output shaft is turning would certainly confuse the ECU.
Don't do that! The only time that should be done is if a software change requires it or solenoids have been replaced, doing so on a 'box that has had no work done can lead to some pretty bad shifts, some 'boxes never achieve their previously 'acceptable but could be better' shift behaviour.
