lockup problem
lockup problem Where should I be looking to solve my trans(4l60e)problem, Was working fine. All of a sudden when the lockup comes in at 45 mph and I'm throttling back it comes out of lockup and stays out till I accelerate again.
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Joined: Aug 2010
Posts: 7,321
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From: Ann Arbor, MI
Why do you think the trans is coming out of lockup when you throttle back?
The overrun clutches are never applied in OD/4th gear, meaning there is no engine braking and it would be hard to feel the difference.
However to answer your question...
You need a scanner that shows/logs the TCC lockup signal to compare what your PCM is command versus what you feel is happening. If the trans/converter is following the PCM commands you know nothing is wrong with the hardware.
If the PCM is commanding unwanted shifts/lockup, you then check sensors and even the tune to determine why it is doing so. In rare cases, the PCM is defective.
The overrun clutches are never applied in OD/4th gear, meaning there is no engine braking and it would be hard to feel the difference.
However to answer your question...
You need a scanner that shows/logs the TCC lockup signal to compare what your PCM is command versus what you feel is happening. If the trans/converter is following the PCM commands you know nothing is wrong with the hardware.
If the PCM is commanding unwanted shifts/lockup, you then check sensors and even the tune to determine why it is doing so. In rare cases, the PCM is defective.