Will not shift into overdrive - gas pedal seems very light - please help!

[lithdoc]

Hello folks,


Seems like my 89 GMQ has started having some transmission issues that will not go away by itself.

It has been happening sporadically for the past 18 months, but would always resolve itself. Normally, my car shifts into overdrive rather roughly, with a big CLUNK! at 45 mph. It is normal for my car from what I've experienced, and I never push the car too hard around the 30-50 mph band to avoid finicky shifting

Sometimes, once every few weeks it would start weird. The gas pedal would feel really light without its usual resistance and the transmission would not shift into overdrive. Normally this would last very short time and cycling the shifter from D to 1 and back would often resolve it. It started again yesterday and unfortunately the usual remedy no longer works.

What could be the issue? Is there an easy fix? Please advise. Thank you.

[lithdoc]

Just to add, the light gas pedal feel will always correlate with my inability to shift, so I can tell whether I'm back in normal, or will the issue continue.

P.S. sorry for a second post - for some reason I could not edit.

[gadget73]

Check the bushing on the bottom of the throttle body. There are 3 cables that hook up there. The two that go together are cruise and throttle. The one towards the middle of the motor by itself is for the transmission. The trans cable is supposed to snap into a bushing that keeps it connected to the throttle lever. If that bushing is missing or falling apart, the trans pressure will be messed up and it may also make the throttle pedal feel light. If its bad, stop driving the car and get a replacement immediately. Driving with no bushing will burn the transmission up.

[lithdoc]

Thank you, will check it out tomorrow. Of note, my cruise control stopped working after winter of '13, maybe that's why? Also, I have this unending hissing sound coming from above the brake pedal area, maybe that has some relation. Please advise.

[VicCrownVic]

Thank you, will check it out tomorrow. Of note, my cruise control stopped working after winter of '13, maybe that's why? Also, I have this unending hissing sound coming from above the brake pedal area, maybe that has some relation. Please advise.

The hissing above the bake pedal would most likely be the cause of your cruise being inop. Either the valve/switch needs to be adjusted or a leak has developed in the vacuum line.

Back to your throttle feel and shifting issue, if you got my text earlier the TV grommet/bushing that I referred to is what gadget73 mentioned as well. Even if the bushing looks good do yourself a huge favor and get a brass one. http://www.ebay.com/itm/Ford-AOD-tra...a40754&vxp=mtr

I believe I have a spare plastic/nylon one in my glovebox that you could have (it came with the car), but I don't know that I'll be able to get it to you before you could have the brass one ordered and in your mailbox. Also the plastic/nylon bushing would be a temporary fix IF it doesn't break trying to install it. When I get a chance I can come over and take a look at what you have going on but that might not be until next week.

Also, if you have the owner's manual I believe it will tell you how to check the trans fluid. It won't hurt to check the fluid level.

[sly]

If you've driven very far with this issue... the transmission may be toast. And by very far, I mean 5-10 miles. Sometimes it'll cook in less than 2 miles. This is if it's the TV grommet going to crap and causing the TV cable to fall off the throttle linkage.

http://lincolnsonline.com/tech/00052.html

[lithdoc]

I've driven around 3 miles, each time 1 mile at a time... The car is now parked.

[sly]

Hopefully it's just the bushing and it's still ok.

sources for acquiring the brass bushing and clip:

http://www.latemodelrestoration.com/item/LRS-7303A/87-93-Mustang-Aod-Brass-Tv-Cable-Bushing-Kit

http://www.ebay.com/itm/like/121628788564?lpid=82&chn=ps

[lithdoc]

Bought it already, thank you... Fingers crossed. She's my beloved daily driver

[cheaneyt]

Bought it already, thank you... Fingers crossed. She's my beloved daily driver

Which site you use? Im gonna replace mine just because . I read the link about this and my overdrive is temperamental. So I wanna make sure mine don't go out.

Sent while thinking of new mods for my 96 TC, using Tapatalk.

[lithdoc]

I bought it on eBay. Came to $14 shipped

[VicCrownVic]

Which site you use? Im gonna replace mine just because . I read the link about this and my overdrive is temperamental. So I wanna make sure mine don't go out.

Sent while thinking of new mods for my 96 TC, using Tapatalk.

Do you have another car besides the 96 TC? This replacement brass bushing would not be compatible with the 96 TC which should have an electronically controlled transmission (AODE or 4R70W I think). The brass bushing is mainly an upgrade for sefi 86-early build 92 CV/MGM with AOD, I'm not sure what year the TC stopped using the old AOD but it was probably somewhere in the range of 90-92 being the last of the AOD in the TC.

[His Royal Ghostliness]

I bought it on eBay. Came to $14 shipped

Holy cow, used to be $5-$6 at the dealer's parts counter, in stock too!!! Granted that was a few years ago, but still, did you even think of calling your local dealer to check if they have it? (obviously this only works if you can actually catch a ride to the dealership and back)

[cheaneyt]

Do you have another car besides the 96 TC? This replacement brass bushing would not be compatible with the 96 TC which should have an electronically controlled transmission (AODE or 4R70W I think). The brass bushing is mainly an upgrade for sefi 86-early build 92 CV/MGM with AOD, I'm not sure what year the TC stopped using the old AOD but it was probably somewhere in the range of 90-92 being the last of the AOD in the TC.

You are correct my bad . Didnt see the engine specs .

Sent while thinking of new mods for my 96 TC, using Tapatalk.

[lithdoc]

It seems that the cable that goes to the transmission is stuck in the permanently out position, which would explain the light throttle