Wait Until You Read This One

Launchnet · 08-12-2006, 10:24 PM

have a 1986 Cad that is in excellant condition except for one problem.

At different times, I can be driving 25 to 30 miles per hour maybe going for 40 or more mph and the transmission shifts into Drive (4th gear on this car) and when you push down on the gas to shift down it won't shift down. When it is in this mode, I can start slowing down and coming to a stop and it won't shift down until I am nearly stopped. When I do stop, and start again, it starts in low gear and when I get to 25 or so it goes into Drive. And, it doesn't do this all of the time.

Manually shifting doesn't change anything.

Transmission is very smooth and does not slip. Engine runs very good, except when in this mode and push down to speed up, the engine seems to bogg down.

This crazy mode seems to happen more often when the engine is warm.

HELP

MaTT

**Fox** · 08-12-2006, 11:35 PM

What happens if you shift into neutral and then back into drive?

daamon_vexion · 08-13-2006, 04:27 AM

and have you checked your tranny fluid?

Launchnet · 08-13-2006, 10:13 AM

Yes, I have tried shifting to neutural and back again to drive. SAME

Yes, we have changed and checked trans fluid. SAME

I think there must be some kind of electronic controller that is not working or something like that.

Thanks for the replys.

Anyone else have any ideas?

Thanks

**bruiser** · 08-13-2006, 10:55 AM

Before you tear into it, get some SeaFoam for the trans. Be sure to get the right one, as there is more than one SeaFoam. Follow the directions and see if it helps. Could just need a little cleaning. If the SeaFoam helps improve the problem, time for a fluid and filter change. I know some of you will say stuff out of a can does no good, but the SeaFoam products are some that actually do tend to work.

**Midnight Tech** · 08-13-2006, 06:24 PM

[shameless product plug]
I second that on the SeaFoam...they have good products.
[/shameless product plug]

Seriously, are you getting a "check engine" light on that car...and if so, have you had codes pulled? Even the '86's on Caddys had a limited bit of computer control over the tranny.

Launchnet · 08-13-2006, 08:39 PM

So far, I have had a very good transmission man pull the valve body and clean it and put in new fluid.

Personally, I don't think cleaning or using seafoam is going to solve the problem. It can run for days and work perfectly. Then all of a sudden it starts to act up.

Please keep trying.

**Midnight Tech** · 08-13-2006, 08:55 PM

I'll ask one of our tranny guys tomorrow if he's ever run into this.

Spacemonkey6401 · 08-13-2006, 08:57 PM

One and only thing that I can think of, and I might be totally off, but I'm throwing it out there, is your torque converter is locking up. It might be locking up around that speed, and then not unlocking. Not real sure what you could do about it, besides replacing it.

daamon_vexion · 08-14-2006, 09:11 AM

Quote:

Originally Posted by Spacemonkey6401

One and only thing that I can think of, and I might be totally off, but I'm throwing it out there, is your torque converter is locking up. It might be locking up around that speed, and then not unlocking. Not real sure what you could do about it, besides replacing it.

i agree, not sure on anything else myself

Bald Eagle · 08-14-2006, 08:22 PM

It is not usually the converter itself that sticks, it is usually one of the controll solenoids that malfunctions. It has been a problem with the fwd GM 4 spds from that era. the solenoids can be purchased separately and replaced.Usually though, they cause the car to stall, acting like you came to a stop in a std. trans without pushing in the clutch. the most common customer complaint was that it stalls sometimes when coming to a stop. You don't say if yours is rwd or fwd. The governor sometime sticks on rwd models and can cause similar problems.

crazijoe · 08-15-2006, 05:47 AM

Try driving it in Drive instead of ODrive.

Launchnet · 08-15-2006, 09:39 PM

I have tried every drive and it makes no difference.

The convertor is starting to sound like maybe that is it. Is there anyway of testing it to see if it is the problem ?

Thanks

Matt

daamon_vexion · 08-17-2006, 04:58 AM

your cad is a rwd v8 right?

Launchnet · 08-20-2006, 11:46 PM

Yes it is a rwd

08-12-2006, 10:24 PM	#1 (permalink)
Launchnet Registered User Join Date: May 2006 Location: Ontario, Ca Posts: 19 OS: XP	Wait Until You Read This One have a 1986 Cad that is in excellant condition except for one problem. At different times, I can be driving 25 to 30 miles per hour maybe going for 40 or more mph and the transmission shifts into Drive (4th gear on this car) and when you push down on the gas to shift down it won't shift down. When it is in this mode, I can start slowing down and coming to a stop and it won't shift down until I am nearly stopped. When I do stop, and start again, it starts in low gear and when I get to 25 or so it goes into Drive. And, it doesn't do this all of the time. Manually shifting doesn't change anything. Transmission is very smooth and does not slip. Engine runs very good, except when in this mode and push down to speed up, the engine seems to bogg down. This crazy mode seems to happen more often when the engine is warm. HELP MaTT __________________ Do you like classic cars? Visit my 1961 Chrysler 300 at: www.openoursite.com It's on my home page.

08-12-2006, 11:35 PM	#2 (permalink)
Fox TSF Enthusiast Join Date: Sep 2002 Location: NJ Posts: 7,752 OS: XP Pro, CentOS My System	What happens if you shift into neutral and then back into drive? __________________ Antec Neo Power 500W, ABIT IP35-E, Intel E2180@2.66Ghz, Corsair XMS2 2x1GB DDR2-800, PNY 8800GT, 320GB Seagate * lazy college student alert *- If I've inadvertently ignored a thread, please Let me know about it Have I helped you solve your problem? Donate to Techsupportforums Klart Skepp!

08-13-2006, 04:27 AM	#3 (permalink)
daamon_vexion Resident Soldier Join Date: Aug 2006 Location: Iraq (temp) Wyoming Posts: 560 OS: Windows XP Media Center My System	and have you checked your tranny fluid? __________________ *And the Infantry Sayeth unto the Lord "Thou hast made us the Queen of battle, and Artillery the King, surely thou knowest what the King does to his Queen?" And the Lord replyeth, "Right On!"*

08-13-2006, 10:13 AM	#4 (permalink)
Launchnet Registered User Join Date: May 2006 Location: Ontario, Ca Posts: 19 OS: XP	Reply to other replys Yes, I have tried shifting to neutural and back again to drive. SAME Yes, we have changed and checked trans fluid. SAME I think there must be some kind of electronic controller that is not working or something like that. Thanks for the replys. Anyone else have any ideas? Thanks __________________ Do you like classic cars? Visit my 1961 Chrysler 300 at: www.openoursite.com It's on my home page.

08-13-2006, 06:24 PM	#6 (permalink)
Midnight Tech Admin/Head GreaseMonkey/Igor's alter ego/Grand Exalted PoohBah Join Date: Dec 2001 Location: SC Posts: 2,920 OS: Windows XP Home/Pro SP3/Windows 98SE/Fedora Core 6/RH 7.2 with Autopoint/TAMS II	[shameless product plug] I second that on the SeaFoam...they have good products. [/shameless product plug] Seriously, are you getting a "check engine" light on that car...and if so, have you had codes pulled? Even the '86's on Caddys had a limited bit of computer control over the tranny. __________________ Please post all questions in the appropriate forum. Questions sent by email or PM will not be answered. Sharing my life...with my Imzadi! Interested in Trek gaming? Check out the Dynaverse! Proud supporter of the Carolinas Aviation Museum. If we have helped you in any way, please donate to keep TSF up and running!

08-13-2006, 10:55 AM	#5 (permalink)
bruiser TSF Enthusiast Join Date: Jul 2005 Posts: 1,973 OS: xp	Before you tear into it, get some SeaFoam for the trans. Be sure to get the right one, as there is more than one SeaFoam. Follow the directions and see if it helps. Could just need a little cleaning. If the SeaFoam helps improve the problem, time for a fluid and filter change. I know some of you will say stuff out of a can does no good, but the SeaFoam products are some that actually do tend to work.

08-13-2006, 08:39 PM	#7 (permalink)
Launchnet Registered User Join Date: May 2006 Location: Ontario, Ca Posts: 19 OS: XP	My Info Update So far, I have had a very good transmission man pull the valve body and clean it and put in new fluid. Personally, I don't think cleaning or using seafoam is going to solve the problem. It can run for days and work perfectly. Then all of a sudden it starts to act up. Please keep trying. __________________ Do you like classic cars? Visit my 1961 Chrysler 300 at: www.openoursite.com It's on my home page.

08-13-2006, 08:55 PM	#8 (permalink)
Midnight Tech Admin/Head GreaseMonkey/Igor's alter ego/Grand Exalted PoohBah Join Date: Dec 2001 Location: SC Posts: 2,920 OS: Windows XP Home/Pro SP3/Windows 98SE/Fedora Core 6/RH 7.2 with Autopoint/TAMS II	I'll ask one of our tranny guys tomorrow if he's ever run into this. __________________ Please post all questions in the appropriate forum. Questions sent by email or PM will not be answered. Sharing my life...with my Imzadi! Interested in Trek gaming? Check out the Dynaverse! Proud supporter of the Carolinas Aviation Museum. If we have helped you in any way, please donate to keep TSF up and running!

08-13-2006, 08:57 PM	#9 (permalink)
Spacemonkey6401 Registered User Join Date: Jul 2006 Location: KS, US Posts: 47 OS: Win XP	One and only thing that I can think of, and I might be totally off, but I'm throwing it out there, is your torque converter is locking up. It might be locking up around that speed, and then not unlocking. Not real sure what you could do about it, besides replacing it.

08-14-2006, 08:22 PM	#11 (permalink)
Bald Eagle Registered User Join Date: Feb 2005 Location: Ontario Can. Posts: 37 OS: winXP sp2	It is not usually the converter itself that sticks, it is usually one of the controll solenoids that malfunctions. It has been a problem with the fwd GM 4 spds from that era. the solenoids can be purchased separately and replaced.Usually though, they cause the car to stall, acting like you came to a stop in a std. trans without pushing in the clutch. the most common customer complaint was that it stalls sometimes when coming to a stop. You don't say if yours is rwd or fwd. The governor sometime sticks on rwd models and can cause similar problems.

08-15-2006, 05:47 AM	#12 (permalink)
crazijoe Registered User Join Date: Oct 2004 Location: Omaha, The Center of the Universe Posts: 7,632 OS: WinXP, Win2K3 My System	Try driving it in Drive instead of ODrive.

08-15-2006, 09:39 PM	#13 (permalink)
Launchnet Registered User Join Date: May 2006 Location: Ontario, Ca Posts: 19 OS: XP	Should I or Shouldn't I I have tried every drive and it makes no difference. The convertor is starting to sound like maybe that is it. Is there anyway of testing it to see if it is the problem ? Thanks Matt __________________ Do you like classic cars? Visit my 1961 Chrysler 300 at: www.openoursite.com It's on my home page.

08-17-2006, 04:58 AM	#14 (permalink)
daamon_vexion Resident Soldier Join Date: Aug 2006 Location: Iraq (temp) Wyoming Posts: 560 OS: Windows XP Media Center My System	your cad is a rwd v8 right? __________________ *And the Infantry Sayeth unto the Lord "Thou hast made us the Queen of battle, and Artillery the King, surely thou knowest what the King does to his Queen?" And the Lord replyeth, "Right On!"*

08-20-2006, 11:46 PM	#15 (permalink)
Launchnet Registered User Join Date: May 2006 Location: Ontario, Ca Posts: 19 OS: XP	Yep Yes it is a rwd __________________ Do you like classic cars? Visit my 1961 Chrysler 300 at: www.openoursite.com It's on my home page.