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lock up issues...

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Old Sep 10, 2006 | 12:37 AM
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From: johnson co.
Default lock up issues...

so...i have a 2000 z28 a4 with most bolt-ons, fuddle 4k stall, transgo shift kit, and tuning (more line pressure, etc) on the tranny, also.

the car shifts perfect, but after lock up - in 3rd or OD - sometimes it acts like it doesn't totally engage the lock up clutch and will slip. other times it will initiate lock up and actually lock. wtf? is this a problem with the hardware, or is it something like the lock up solonoid? the converter has maybe 10k on it, has never been locked up for dyno pulls or anything, and has performed flawlessly up until now.

it is an el cheapo ($400) fuddle converter, hasn't given me a second's worth of trouble, and has generated excellent results at the track and on the highway. the search function didn't provide me with any concrete answers.

thanks in advance...
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Old Sep 10, 2006 | 10:47 AM
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t t t
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Old Sep 11, 2006 | 06:18 AM
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t t t

anyone?
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Old Sep 11, 2006 | 07:50 AM
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Default

Totally refusing to lock, or lock/unlock based on load
point away from the set speeds, is probably misfires.
A soft slip while locked is low line pressure starving
the TCC, possibly also the PWM function further
degrading the available lock force. Both of these would
be addressable with tuning.
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Old Sep 11, 2006 | 10:46 AM
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the trans has a transgo shift kit and has had the line pressure increased. i've ran on this setup for ~10k or so with no trouble until now.

last week the lock-up was "acting up" in the sense that it was totally unlocking for periods of time ranging from 1-3 minutes...but eventually locked with no slip.
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Old Sep 11, 2006 | 01:12 PM
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That's almost certainly misfires. Might be as simple as a
flaky spark plug wire end-clip, or not. It doesn't need to
be bad enough to set the light, to mess with the
converter.
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Old Sep 11, 2006 | 04:43 PM
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hrm...i guess i have something to do this weekend.
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Old Sep 17, 2006 | 02:11 AM
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ok, so i checked the plugs/wires, everything is ok. the plugs only had ~3k on them, i replaced them when i installed the longtubes.

so after extensive testing tonight - i drew this conclusion:

soft-med accel = half-*** lockup
med-hard accel = complete lockup, no slip.

is this a solonoid problem or what? i can feel the difference in lockup, as the "complete" lockup will jar the car and obviously drag the rpm way down...whereas the "half-***" lockup slowly pulls the rpms down (and revs up if i give it gas..)
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Old Sep 17, 2006 | 10:54 PM
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....anyone?
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Old Sep 17, 2006 | 11:56 PM
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This is standard stock TCC PWM action and perhaps
the standard stock 0%-commanded line pressure as
well. I took out the PWM and bumped line up for my
old converter.
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