Tcc lock up

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90hurst/oldsguy

Greasemonkey
Jan 31, 2013
165
18
18
What will cause the tcc lock up in 200r4 to stick and not release? This trans has been rebuilt in 2015 and has had new tcc lockup solenoid and it stays in engage when the car is slowing down.
 
Does it ever release or does it stall the engine?
 
First, check to see if you get voltage to the solenoid and that it's not on all the time. If that checks out then it might be a bad solenoid that has stuck open or a bad TC. It's less likely, but there's also a brake switch that could be causing your troubles.

If you're not controlling your trans with an ECU then the problem could be an internal pressure switch (4th gear). The pressure switch should release the TC clutch when the trans downshifts to third, but may continue to feed the TC if it fails.

Typically, when the solenoid is bad enough to cause stalling the TC gets damaged and will exhibit the same issues either immediately or later down the road due to the clutches going south.

Regardless of whether the source of the issue is the pressure switch, the solenoid, or even something else I'd very seriously consider buying a new torque converter.
 
Unplug the connector from the transmission. If the problem goes away it's electrical, if it continues it is inside the transmission.
I have checked without the tcc connector unplugged and trans shifted better.ive been wondering if it's been the tcc apply valve.
 
First, check to see if you get voltage to the solenoid and that it's not on all the time. If that checks out then it might be a bad solenoid that has stuck open or a bad TC. It's less likely, but there's also a brake switch that could be causing your troubles.

If you're not controlling your trans with an ECU then the problem could be an internal pressure switch (4th gear). The pressure switch should release the TC clutch when the trans downshifts to third, but may continue to feed the TC if it fails.

Typically, when the solenoid is bad enough to cause stalling the TC gets damaged and will exhibit the same issues either immediately or later down the road due to the clutches going south.

Regardless of whether the source of the issue is the pressure switch, the solenoid, or even something else I'd very seriously consider buying a new torque converter.
Well this trans has been rebuilt but it definitely doesn't sh*t into drive correctly its more of a bang... The guy left out a wave plate in the transmission
 
I bet he did more than that. There's a million ways to build these things and everyone has a different preference, but it's common to change all sorts of things regarding accumulators, springs, steels, etc.. as well as orifice sizes or even plugging passages.
 
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Sounds like one of the servo springs as well. Ask if he installed the wide band? And not just the stock narrow band.

Along with that several of the OEM pistons were plastic and they shatter. You replace with cast aluminum or billet, billet being better. This sounds like a case of if you don't know what you are doing ... Don't touch it.

Leaving out the wave steel should not make it bang into gear. It will be firmer and about .25 seconds quicker, but not bang. Drilling the apply in the plate too large and leaving out the accumulator spring will make it "bang" along with breaking things.

Possible you got some crud in the valve body making TCC stick.
 
Sounds like one of the servo springs as well. Ask if he installed the wide band? And not just the stock narrow band.

Along with that several of the OEM pistons were plastic and they shatter. You replace with cast aluminum or billet, billet being better. This sounds like a case of if you don't know what you are doing ... Don't touch it.

Leaving out the wave steel should not make it bang into gear. It will be firmer and about .25 seconds quicker, but not bang. Drilling the apply in the plate too large and leaving out the accumulator spring will make it "bang" along with breaking things.

Possible you got some crud in the valve body making TCC stick.
The guy that built the transmission was a gm technician and I'm pretty sure it doesn't have the wide band. I think it's time to replace it with better built 200r4 since there isn't many people in my area that wants to touch them etc
 
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