4L60E lockup problem...
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From: Spencerport, NY
4L60E lockup problem... I had a B&M 2400 stall TC in the car I had noticed that the TC was never locking up so last weekend I replaced it back with the stocker. And the stocker isn't locking up either. I had this problem before I changed out the computer and still with the tuned one in it now. Could there be a wiring problem or something else I am overlooking? The car does seem to move a little easier now that the stock converter is back in it but its not locking up once I get up to speed.
Could be the TCC solenoid or PWM solenoid. I have the same problem and my whole tranny is taken apart right now for a rebuild. I haven't got around to testing my solenoids yet, but I'm hoping it's the PWM.
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From: Spencerport, NY
So there really isn't anyway to find out or fix this issue without a tear down then? well that sucks, I have the 94 Trans that needs new clutches hoepfully thats all and I can fix that and swap that in over the winter...
OBDI sucks *** for diagnosing. I'm not throwing a code and my converter won't lock either.
The very least you can do is drop the pan and replace some solenoids. It should be one of those two solenoids and not the converter since you switched them. I have access to a solenoid tester, but I wouldn't know where you can find one. You could just go ahead and replace them, but I'm not a fan of replacing something without diagnosing it first. I'll test my solenoids this week and then I'll be able to steer you in the right direction as far as fixing the problem.
Also, very important. Does your cruise control work? That will let you know if the brake switch is stuck open.
The very least you can do is drop the pan and replace some solenoids. It should be one of those two solenoids and not the converter since you switched them. I have access to a solenoid tester, but I wouldn't know where you can find one. You could just go ahead and replace them, but I'm not a fan of replacing something without diagnosing it first. I'll test my solenoids this week and then I'll be able to steer you in the right direction as far as fixing the problem.
Also, very important. Does your cruise control work? That will let you know if the brake switch is stuck open.
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Possibly. All you have to do is give it about 5volts to energize it and use a air gun to blow air through it. You will need to rig up a pressure gauge because you want to see what the PSI is at with it on and off. You have to be careful with the PWM solenoid though. Put a C-clamp on it because it can shoot off.
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You can test them under normal driving conditions with a 2 channel scope and a scanner with bi-directional control.
With the scope hooked up, you can see if the computer is commanding lockup, and the scope will show you if everything is happening electrically. Then if its not commanding lockup, using the bi-di controls you can activate them and see if it happening electrically.
If all you're going by is it isnt locking up, theres so many things it could be. It could be the harness, the computer, something else telling the computer not to lock it up, a fluid pressure leak like a ripped o-ring on the shaft. A bad clutch in the TC (seen that once).
With the scope hooked up, you can see if the computer is commanding lockup, and the scope will show you if everything is happening electrically. Then if its not commanding lockup, using the bi-di controls you can activate them and see if it happening electrically.
If all you're going by is it isnt locking up, theres so many things it could be. It could be the harness, the computer, something else telling the computer not to lock it up, a fluid pressure leak like a ripped o-ring on the shaft. A bad clutch in the TC (seen that once).
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Joined: Sep 2006
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From: Spencerport, NY
OBDI sucks *** for diagnosing. I'm not throwing a code and my converter won't lock either.
The very least you can do is drop the pan and replace some solenoids. It should be one of those two solenoids and not the converter since you switched them. I have access to a solenoid tester, but I wouldn't know where you can find one. You could just go ahead and replace them, but I'm not a fan of replacing something without diagnosing it first. I'll test my solenoids this week and then I'll be able to steer you in the right direction as far as fixing the problem.
Also, very important. Does your cruise control work? That will let you know if the brake switch is stuck open.
The very least you can do is drop the pan and replace some solenoids. It should be one of those two solenoids and not the converter since you switched them. I have access to a solenoid tester, but I wouldn't know where you can find one. You could just go ahead and replace them, but I'm not a fan of replacing something without diagnosing it first. I'll test my solenoids this week and then I'll be able to steer you in the right direction as far as fixing the problem.
Also, very important. Does your cruise control work? That will let you know if the brake switch is stuck open.
On a side note its funny how I have recieved more feed back on this same thread under the LT1 section than I have so far on the Automatic's section...
Thanks for your feedback so far guys! Thread Starter
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From: Spencerport, NY
It seems to shift just fine through all the gears and on time. Although I have changed around the shift points with the Hyper-tech tuner I changed the 1-2 shift for 6mph early and it goes right to red line before shifting, and all the rest of the shifts I changed 1mph early since before the TC change it seemed to not shift occasionally on time and was/is worse with the exhaust cutout open...
Yeah my car was not equiped with the cruise control... I don't think the solenoids are the reall issue here either though, not to say that it isn't possible. However the transmission worked perfectly when it was in the 96 when I had that, I also had for a long time a SLP wire-tapped shift improvement module, I loved it too! So I heard from Perforambuilt that its electrical since 96 has PWM and the 94 does not. The 94 does not have the wiring for the PWM. He told me to email him on an easy fix for that but I have not hear back from him yet (emailed him a day ago).
On a side note its funny how I have recieved more feed back on this same thread under the LT1 section than I have so far on the Automatic's section... Thanks for your feedback so far guys!
On a side note its funny how I have recieved more feed back on this same thread under the LT1 section than I have so far on the Automatic's section...
Thanks for your feedback so far guys!I just tested my PWM solenoid and TCC solenoid today. Unfortunately, they work good, which leads me to believe it's a torque converter failure. My whole tranny is in pieces from seal to seal and there doesn't seem to be any internal failure.
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From: Spencerport, NY
A 94` 4l60e does to have a PWM. I don't know what perforambuilt is talking about.
I just tested my PWM solenoid and TCC solenoid today. Unfortunately, they work good, which leads me to believe it's a torque converter failure. My whole tranny is in pieces from seal to seal and there doesn't seem to be any internal failure.
I just tested my PWM solenoid and TCC solenoid today. Unfortunately, they work good, which leads me to believe it's a torque converter failure. My whole tranny is in pieces from seal to seal and there doesn't seem to be any internal failure.
Oh maybe you can explian to me where the PWM and TCC solenoids are and where they are. I helped rebuild the 94 trans when my friend owned it but I don't remember it all that much.
Well my 94 has a PWM, so I don't know what to tell you.
The TCC solenoid just turns the torque converter clutch on and off. The PWM cushions the lockup by pulsating it just like a fuel injector turns on and off. Old cars without a PWM would slam into TCC lockup. It takes some knowledge and tools to rebuild a tranny, but switching/testing solenoids isn't hard. They are held into the valve body by a clip. Every solenoid has a connector on it except for the TCC, for which it is part of the wiring harness.
The TCC solenoid just turns the torque converter clutch on and off. The PWM cushions the lockup by pulsating it just like a fuel injector turns on and off. Old cars without a PWM would slam into TCC lockup. It takes some knowledge and tools to rebuild a tranny, but switching/testing solenoids isn't hard. They are held into the valve body by a clip. Every solenoid has a connector on it except for the TCC, for which it is part of the wiring harness.
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From: Spencerport, NY
Yeah I might remember when I look inside it. If I get the energy I might look at it soon. Assuming that that is the real issue with it... Thanks for the help and good luck with your transmission!
I guess Performabuilt was right. My PWM solenoid isn't for the converter lockup. They use it for the 3-2 downshift and 2-4 band apply. So there is a PWM, but not using it for converter lockup.
Good luck
Good luck
