700R4 question
Thread Starter
Melting Slicks
Joined: Jun 2011
Posts: 2,096
Likes: 15
700R4 question
Ok this is driving me nuts. I have a 82 with the original 700R4 and the lockup does not engauge. Sometimes it will when I first start it up for the first time of the day and it reaches temp but will immediately disengauge. I replaced the solenoid, the TCC switch and the 4th gear switch. The tranny shop told me that the computer wasn't sending the ground to the solenoid. They told me it could be fixed for $200 but then said they wouldn't garantee it. When I asked what they were gonna do he said it was a secret. Because of that I did not have then touch it. So after replacing those items could it be something in the ECM or PCM whatever you want to call it??? Other than that the tranny shifts great.
Advanced
Joined: Mar 2005
Posts: 58
Likes: 0
I have had 3 82's and the lock up even when it's working perfect does not work to good.It lock's up to early,then when u give it a little gas the engine shutters,just a nightmare.What I would do first is jump a wire between pins a and f on the diag connector behind the ash try .This is so easy to do this will force the converter to lock up.See if that works.That will prove if the tranny is ok.Then u can go from there Call me if u want danny 754-422-3497.I have been down this road many times.
Team Owner
Joined: Jan 2006
Posts: 37,637
Likes: 3,118
From: Crossville TN
It sounds like the lockup clutch is functioning in reverse of how it should. When cold, the L/U should NOT come on. When the engine is warmed up, it SHOULD come on. Perhaps the temp switch that sends the "warmed up" temp signal to the computer is wired backwards or the wrong unit was installed the last time it was replaced.
Thread Starter
Melting Slicks
Joined: Jun 2011
Posts: 2,096
Likes: 15
I think I confused everyone. The lockup will engage for a couple of seconds on my first startup of the day BUT after when the car reached temp. Meaning it is warm. Sorry for the confusion. And thanks Dannys8 I will try that out today.
Thread Starter
Melting Slicks
Joined: Jun 2011
Posts: 2,096
Likes: 15
I have had 3 82's and the lock up even when it's working perfect does not work to good.It lock's up to early,then when u give it a little gas the engine shutters,just a nightmare.What I would do first is jump a wire between pins a and f on the diag connector behind the ash try .This is so easy to do this will force the converter to lock up.See if that works.That will prove if the tranny is ok.Then u can go from there Call me if u want danny 754-422-3497.I have been down this road many times.
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Thread Starter
Melting Slicks
Joined: Jun 2011
Posts: 2,096
Likes: 15
Well what I thought was fixed still isn't. But here are the clues. When A and F are jumpered the lockup engages, my cruise switch is adjusted right so that leaves me with a possibly bad ECM?? I don't know where to go from here.. Any suggestions??
Team Owner
Joined: Jul 1999
Posts: 65,492
Likes: 230
From: Orange Park Florida
I am not familiar with your stock '82, so question is.....do you have a 'external-inline' sending unit?? one that contains the sending coil and inserts itself in between the usual stock speedo cable and the typical tranny output from the speedo gearset??
THAT is what I had and just finished battling the thing....carefully open up the sending unit, mine was aftermarket.....look at the spinning magnet assy...you maybe well find that it's possible to activate your mechanical speedometer, and still have that magnet assy not spin...due to craziness of it's construction....drove me nutz for several days, me convinced with the temp, and intermittent operation that I had it fixed, but a day later it would not lock, especially on the freeway....it was giving the computer a very messed up, intermittent speed signal, while the dash looked normal....
I was ROCKET PISSED when I found it, talk about sneaky, that's IT!!!
damnit!!!!!
:hide :
THAT is what I had and just finished battling the thing....carefully open up the sending unit, mine was aftermarket.....look at the spinning magnet assy...you maybe well find that it's possible to activate your mechanical speedometer, and still have that magnet assy not spin...due to craziness of it's construction....drove me nutz for several days, me convinced with the temp, and intermittent operation that I had it fixed, but a day later it would not lock, especially on the freeway....it was giving the computer a very messed up, intermittent speed signal, while the dash looked normal....
I was ROCKET PISSED when I found it, talk about sneaky, that's IT!!!
damnit!!!!!
:hide :
Burning Brakes
Joined: Mar 2010
Posts: 943
Likes: 15
From: Valdosta Georgia
I think that the speed sensor for the 82 is on the speedo itself in the dash, others will correct me if I am wrong. The signal comes from there and goes to the ecm. Check it out, there is a sensor attached to the rear of the speedo.
Thread Starter
Melting Slicks
Joined: Jun 2011
Posts: 2,096
Likes: 15
I really don't know how to check it but did have it unplugged and plugged it back in. Is there a way to check this?? I did recently buy a NOS speedo sensor in case mine was bad. Was told though that these hardly ever go bad...
Last edited by alconk; May 27, 2012 at 10:14 PM.
