88 4+3 OD shift button not working
Thread Starter
Instructor
Joined: Oct 2001
Posts: 152
Likes: 0
From: Walnut Creek CA
88 4+3 OD shift button not working
I have an 88 with the 4+ 3 tranny. There is a button on the shifter that lets you manually turn on and off the OD unit outside of the normal parameters that automatically turn on and off the OD unit. Unfortunatley my button does not do anything and I am not sure where to start. When I bought the car 2 years ago from the original owner it did work, but now does not. Could it be something simple like the button is not working, or should I start at the tranny (the OD unit) and work my way back to the button?
Thanks
88 4 +3 Charcoal Metallic
145,000 and still pulling like a freight train!
Thanks
88 4 +3 Charcoal Metallic
145,000 and still pulling like a freight train!
Thread Starter
Instructor
Joined: Oct 2001
Posts: 152
Likes: 0
From: Walnut Creek CA
yeah Scorp, it will still kick down when I get on the gas (or any of the conditions that trigger the on/off) I just cant manually turn it on or off with the shifter button. I am hoping it is something (cheap) like the button or a lose wire, but I figure someone out there might have been down this road before...
Thanks!
Thanks!
Drifting
Joined: Aug 2001
Posts: 1,550
Likes: 27
From: Minneapolis MN
I had my OD switch fall off the shifter and hence the OD button would not do anything. You have to remove the console and shift boot to take a look, real easy.
I can't remember how but I managed to get the switch back on the shifter, and it now works.
I can't remember how but I managed to get the switch back on the shifter, and it now works.
Team Owner
Joined: Mar 2001
Posts: 54,124
Likes: 30
From: Cincinnati, Oh USA
Your switch mounting may have become loose or through normal wear and tear, the adjustable rod that connects the button to the switch may need to be readjusted. And last, the switch is fragile and may be broken and require replacement. You can dissassemble your shifter and look at the switch to determine if its mounting nut is loose or that the switch is broken. A new switch can be obtained FAR cheaper than at GM from Mouser, www.mouser.com and is their part number 506mpa 106F for $12.80 plus shipping.
Gently pull up on the front of the button with a wide screwdriver, then with pliers, pull out the wedge at the rear of the shaft and unscrew the shifter ****. You need to pull up the console plate to see the lower part of the shifter and where the switch is located. Good luck.
Gently pull up on the front of the button with a wide screwdriver, then with pliers, pull out the wedge at the rear of the shaft and unscrew the shifter ****. You need to pull up the console plate to see the lower part of the shifter and where the switch is located. Good luck.
6th Gear
Joined: Feb 2003
Posts: 6
Likes: 0
From: Saddle Brook NJ
I have the same exact problem. The tranny seems to work like it's supposed to, as far as automatically downshifting when you get on the gas, but the button doesn't do anything. I tested the momentary button (The car came with a B&M T- handle with a side button when I bought it) with a test light and it seems to be working. Does anybody know if there is a switch somewhere, that could be bad?
Racer
Joined: Jul 2000
Posts: 363
Likes: 11
From: St. Catharines Ontario CANADA
Check the wires to the OD relay...the insulation shrinks back and they short out. The relay is located on the firewall just a tad drivers side of center (at least it is on my 86). I found 2 inches of bare wires that were all wrapped together on mine.
Last edited by redvette1986; Aug 3, 2004 at 01:06 AM.
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Team Owner
Joined: Mar 2000
Posts: 83,383
Likes: 87
From: Boston, MA
If the computer is still controlling it properly (as it sounds) then just your switch is fried. You can get the one from mouser or you can get one from www.newark.com for about the same price. You'll have to solder the stock harness onto it, but you really have no choice as I think GM discontinued the switch with the harness recently. Its a good thing too because GM wanted almost $100 for it!!!!
