89 XR-7 - transmission won't shift

hulakai

Registered User
Hey all. I've tried searching many times and can't seem to find anything that matches the problem I'm having so I'm going to chance getting flamed for not researching first and go ahead with a new thread...

I bought an 89 XR-7 for my son. Car is a little rough, and it sat for years, but I only paid $400 for it and after a fuel pump and filter change it started right up and runs surprisingly well...so I'm committed to finishing the mechanical work and then if he wants to restore it, that's up to him.

So here's the problem....it won't shift right. The first time I took it for a run it wouldn't shift at all but eventually it did....sort of. It will shift from 1st to 2nd but that's it.

There is a shudder that seems to come from the back end when accelerating around a corner and when downshifting from 2nd. I can't tell if it's a torque converter shudder, or the rear end, or a u-joint, or driveshaft issue, or what.

It has some instrumentation problems too, which I won't get into right now, that includes the speedo, tach and fuel gauge. There is power to the tach (it jumps when I turn the ignition on) and the fuel gauge (reading full but it's not full....and it's a new fuel pump/sender assembly). I can't be sure if there's power to the speedo or not (how can I tell?).

Based on the speedo not working and it not shifting, I assumed (despite the fact that the tach and fuel gauge aren't working right either) that it was the VSS causing the shift/speedo problem and the fuel gauge and tach are separate issues. However, I replaced the VSS and there hasn't been any change to the shifting or the speedo problem so maybe that was a foolish assumption. Is there actually some bigger that could cause the speedo, tach, fuel gauge AND shifting to misbehave? The temp and oil gauges DO work btw.

We had to change the ignition switch on the column (typical Ford problem...the switches on my 85 TC and even my 81 'bird wore out too), so I wondered if the boy had disturbed a ground somewhere and maybe that was part of the problem. So yesterday I took the entire dash apart and removed the cluster. I didn't find any unusual or loose grounds.

I haven't gone through each individual wire from the plug on the VSS all the way to the inside of the car with a meter yet (that's tomorrow's plan) but SOME of the wires are connecting because the car wouldn't start when I disconnected it (neutral safety sensor I assume?). I have all the electrical schematics for the car so I should be able to verify every connection (eventually).

The guy I bought the car from CLAIMED that it was driving until the fuel pump failed and that's when he parked it. If that's true (and it might not be) then the shifting problem is 'new' in the sense that many years ago (10+) the problem wasn't there.

Am I right in thinking that the transmission should still shift even without the cluster because the signal from the VSS is split BEFORE the speedo and the computer should still be telling the transmission to shift regardless of whether there is a speedo hooked up or not? Am I wrong to assume this?

Last time I checked for computer codes there weren't any...but my understanding of early OBD cars is that you don't get nearly the same amount of information from the computer that you do today. All I have for checking OBD1 codes is one of those cheap manufacturer-specific code readers, which I assume aren't that good.


So until I can update the thread with the results of some basic wiring traces, I would LOVE it if anyone has some a) troubleshooting tips/steps that I can follow, or b) some specific things to look at or try in order to isolate the issue.

I'm hoping this site is still frequented often and there's remains a good following of SCs (and XR-7s) out there. Around the same time I bought the XR7 for the boy I also found myself a 92 SC that's been stored indoors for several years and is in EXCELLENT shape. It's completely stock so I'm looking forward to updating and modding that one next year using info and help from this site.

Thx

K
 
Might want to search here on AOD TB cable adjust - it's pretty straight forward, but you don't want to get creative or you can bake the trans in short order. First thing to do is make sure the cable is still attached at the throttle body. Then have someone work the pedal to confirm the cable isn't hanging in the sheath. Then do the adjustment. Speak up if you can't find it. Amounts to engine off, keeper clip on cable end released, slight tug on cable end to remove slack, set cable keeper locked, done. Replace the cable-to-throttle body linkage bushing if sloppy/missing.

See the two cables on the linkage - top one is the TB cable to the trans:
attachment.php


Shudder when cornering might be mounts and/or stuck diff plates, bad wheel bearings...the list goes on. These cars don't like sitting around, so it might just be a matter of putting some miles on it. Sanity check the suspension and tires, lug nuts etc. Make sure the diff oil is up, but if it's been a while, I'd add diff fluid treatment from Ford, and then oil to bring it back up if the level is still low.

All I have for checking OBD1 codes


They all do the same thing. Not sure one is any better or worse than the other as long as it's something you understand how to use to pull codes. SC specific code list is here, BTW: http://www.njtacc.com/tech/eec_codes.html
 
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Prepare for a new trans!

The trans in that car is an AOD, which I generally prefer to call a DOA. It is an entirely mechanical trans, and not dependent on any electrical signals, or power or ground. The TV cable was already mentioned, and if it is stuck wide open, it could cause a late shift out of first and possibly no shift out of 2nd, but that isn't how they typically fail. Usually the cable comes detached from the throttle body linkage, which keeps the line pressure in the trans low, which quickly burns out the trans. At this point, I would start by looking to make sure the TV cable is hooked up properly. If it is, and you still have this issue, your trans is toast. If the TV cable is not hooked up properly, re-attach it properly and test drive the car. At that point, if the trans is working properly, you have resolved the issue, but if it is not, then your trans is toast.
 
Hey all. I've tried searching many times and can't seem to find anything that matches the problem I'm having so I'm going to chance getting flamed for not researching first and go ahead with a new thread...

I bought an 89 XR-7 for my son. Car is a little rough, and it sat for years


K


See if this helps.


What is the condition of the ATF and what was the dipstick reading before and after the road test? Have you inspected the transmission pan for clutch and or metal debris? Has the radiator coolant color changed to a "greasy" pink? If so you could have a bad radiator/cooler failure. I would start there first. It has been my experience that previous owners never put extra emphasis on routine ATF changes based on driving conditions or put higher quality ATF when it was changed. Might have built up varnish within the valve body that could require an additive (such as @ Seafoam Trans Tune and or LUBE GARD red) to address the problem of shift and or shudder.


As for the instruments (RPM, Speedometer) issue I would remove instrument cluster and clean the electrical connectors first. Then remove the RPM and Speedometer gauges and clean the backside circuit "cards" with @ CRC QD electrical cleaner. Re-install can try again.


Good Luck.
 
Welcome to the club! You've joined in one of the slower times for the forum...many are putting their cars away for the winter, we had our big club meet in October but the racing got rained out, so bench racing is slow this year too. :D Good luck figuring it out...it will be sweet having a father/son SC duo. :)

If your car sat outside for many years and depending on where you live, corrosion is going to have caused plenty of degradation in different places. Especially if moisture got into the car and was pretty well trapped.

I second the suggestion to check the instrument cluster connections...it's possible that they are 3 individual problems, but it sounds like a instrument ground (gray/red) wire may have a poor connection somewhere. I'll try to look in my factory EVTM manual to help you have an idea of where to look specifically, since you've already done a general check. Maybe somebody else can check faster.

For the transmission, as has already been said, shift control is completely mechanical and relies very heavily on the TV cable position and proper adjustment is key. Don't drive it if it's not acting right! :eek: Make sure that TV cable isn't stuck or broken. Being it sat for so long, I could see the TV cable getting rusty and stuck and/or breaking. A common fail point is at the throttle body connection, but your symptoms don't exactly match the expected for that issue. Anyways, check it over very well...it's not hard to guarantee it's working! ;)
 
Wow...I didn't expect such great and detailed responses so quickly. Thanks very much. Your replies have prompted me to remember some more info, and ask a question...

First the question: Is the VSS solely for the speedo and cruise control then? I thought it was related to shifting as well....although I must admit I was surprised at this idea when I first read about the VSS because I put an AOD in my 81 bird and it CERTAINLY didn't have any electrical connections (it came out of an 86 cat, along with the interior and a built-up engine. Broke a few Mustang owners' hearts with that butt-ugly sleeper lol)
So the various other Ford articles I have read about the VSS causing shift problems don't apply to this car? Fair enough...

So regarding new info I have remembered after reading your replies...

As I said, the car sat for a LONG time...perhaps over 10 years but I can't verify if the guy was telling me the truth. When we first got the car running, two things came to light:

- the rad had a pinhole leak in one of the tanks. The rad was removed and professionally repaired (man those rads are expensive to buy!) so the coolant is fresh AND I can say for sure that the coolant was VERY clean when we removed the rad.

- the trans was extremely low on fluid. If memory serves (this project has been ongoing since June), we ended up putting close to 5 litres of trans fluid in it before it was full. I thought this was odd and I fully expected to find a leak once it was filled again, but no such thing. Bottom of the trans and all around it are bone dry. Can trans oil evaporate over years? Seems unlikely to me but I'm no expert whatsoever. Point is, the trans fluid is clean and fresh but I can't say if there's anything in the pan and I can't comment on the original color of the fluid...BUT after refilling, the fluid is the color one would expect i.e. it hasn't been darkened by the presence of old/burned fluid prior to putting in fresh.

The cable thing on the TB is new to me but make perfect sense (duh!), so thanks very much for educating me on that. I guess I've been driving cars and trucks with full electronic drivetrain controls for too long! I will be looking at that this afternoon. The cable theory makes the most sense to me so far if the AOD has absolutely no electronic shifting control because on one of the test drives the car actually DID shift relatively ok. Also, when we THOUGHT we had solved all the basic issues and didn't know the trans was having problems, the boy took the car to his friends one night and it shifted ok on the way there, but not so good on the way back and it got even worse after that so I told him to park it before he trashed the trans (hopefully it's not trashed already). So if that cable is not connected properly or loose or out of adjustment, it might explain why it shifted ok for a brief period.

I should mention that all the other issues (tires, brakes, etc) were all addressed prior to putting it on the road. Safety first.

Funny that the AOD is despised so much. When I had my 81 and put the 86 AOD in it (along with the floor shift) I absolutely loved it. Start out in 1, shift to D and back to 1 real quick and it would slam into 2nd gear really solid. Great for those impromptu runs against 5.0 Mustangs at the lights and the AOD never let me down. I know, I know...why would I bother with an 81....but I was in high school and money was tight.

Thanks again...I'll update tonight after I look at that cable.
 
Almost correct, the VSS is used by the ECM to adjust idle speed and ignition timing, as well as being used for the speedo and cruise, so lack of VSS signal can still cause some drivability issues, but they would be more along the lines of stalling or holding a high idle, and would not affect the shifting. The AODE/4R70 are the transmissions that came after the AOD, and they are fully computer controlled, and a huge improvement on the AOD in every way. If your trans is done, I highly reccomend replacing it with a 4R70 instead of another AOD, however that will require either a different computer and significant re-wiring and tuning, or a stand-alone transmission controller.

As for the fluid evaporating, no that doesn't happen, but sometimes rubber seals will dry up and leak from sitting for a long time, and at least in theory they could then swell up again once the fluid starts flowing.
 
- the trans was extremely low on fluid.

I'll assume the 5 qts (ouch) went in first, then the drive where shifting acted up. If the cable bushing & adjustment are ok, then it might be another excuse to put some miles on it. That and a 4 qt fluid change is all my '90 SC w/AOD at 110k miles has needed so far; not that I drive it much these days. Strange the outside didn't show leaks...those 5 qts had to go somewhere ;) Can you tell if the trans has ever been out of the car?

Still no joy, might be time to drop the pan and inspect for atypical debris, then go from there. I suspect, tho, that ten years aging in the barrel hasn't done the insides any favors. Keep driving it/heating it up, maybe some fluid treatment to help swell the seals etc. Note that full fluid changes for some ended up being ill advised, as the increased acidity can loosen build up that leads to trans fail. I think our AOD holds around 12 qts. total, so 5 new shouldn't be an issue.
 
Thought I'd pop in with another update....

The more I thought about it the more I feel like an idiot. I used to have an 86 AOD. Why the hell did I think an 89 would be any different ie electronic shift controls? Dumb dumb dumb. I've been out of this for too long and made the mistake of listening to the boy when he did own research on the problem. Clearly he was reading about a much newer and different trans.

I just went outside to have a quick look at the linkage and it's COMPLETELY DISCONNECTED AT THE TB.

Dumb dumb dumb.

Now on to the gauge problems.

Thanks again guys

K
 
it's COMPLETELY DISCONNECTED AT THE TB.

Let's hope the trans is ok. Keep us posted ;)

About the speedo - there are small plastic gears inside the speedo head that crumble with age. A fairly common fail. That would be one of the things you need to check. Search here on that topic. Might be $60 for news ones, last time I checked.
 
Thought I'd pop in with another update....

The more I thought about it the more I feel like an idiot. I used to have an 86 AOD. Why the hell did I think an 89 would be any different ie electronic shift controls? Dumb dumb dumb. I've been out of this for too long and made the mistake of listening to the boy when he did own research on the problem. Clearly he was reading about a much newer and different trans.

I just went outside to have a quick look at the linkage and it's COMPLETELY DISCONNECTED AT THE TB.

Dumb dumb dumb.

Now on to the gauge problems.

Thanks again guys

K

Easy Fix! :)

Pick up a new one of these....don't try to reuse (if it's still even there):

tv.PNG

Or better yet....one of these:

https://www.ebay.com/i/112654932958?chn=ps

Bill Evanoff at Supercoupeperformance.com may be able to price-match or beat the lowest price you'll find elsewhere. I bought a couple from him in the past.
 
Did you have any luck reconnecting the TB cable? If you need to replace the bushing, I'd not bother w/plastic - spend the money for brass, instead. Search here for details.

Finding the trans low 5 qts, and the cable not connected makes me wonder more if that trans was a swap. Maybe a previous owner simply didn't finish a job they started.
 
So great to have so much input, thanks guys.

I haven't been able to spend a ton of time on it the last couple of days, but I did a bunch of testing....drive, stop, adjust, drive, stop, adjust...and I was able to get it shifting up through all 4 gears at what I would call 'normal' shift points. However, the downshifting wasn't even close to right and I'm 99% sure it's because I don't have the right bushing on the throttle lever where the TV cable connects. When I found it disconnected, the bushing was also gone so I used a stiff rubber grommet to get it working, but in my testing I have realized how sensitive the adjustments are (no wonder the teeth on the end fitting are so close together) so I have no doubt that the flex of the rubber grommet is causing my adjustments to only be effective on either the up shifts or the downshifts because of the flex in the rubber. As soon as I let off the throttle the grommet is flexing first and so the TV cable is instantly out of adjustment on the way down.
I also noticed that the inner plastic sleeve that the cable itself goes into is broken right where it goes into what I'll call the 'anchor' of the cable where it connects to the stationary bracket. So I'm going to try and get a whole new cable, bushing included...and hopefully a brass bushing at that but where I live sometimes I have to take what I can get.

I think the diff is definitely the source of the shudder...it only happens around corners. Am I right? I think I'm going to take it in to a quick lube place and get them to change the fluid. It's too damned cold here right now to be laying under a car trying to drain and fill thick oil. Will quick lube places know enough to put in the right additive when changing diff fluid, or should I pick up the additive myself at Ford and TELL them to put it in?

I'll keep you posted as I work through this...just not sure how long it will take for me to get a cable and bushing. Local dealer is guaranteed to not have it in stock.

Thanks again for the help. I'm glad there's still lots of guys on here. Can't wait to start working on my SC in the spring and do some fun things to it vs just trying to get this Cat driveable!
 
Easy Fix! :)

Pick up a new one of these....don't try to reuse (if it's still even there):

View attachment 68022

Or better yet....one of these:

https://www.ebay.com/i/112654932958?chn=ps

Bill Evanoff at Supercoupeperformance.com may be able to price-match or beat the lowest price you'll find elsewhere. I bought a couple from him in the past.



Where is this listing from? It looks like Rock Auto but I don't see a Shift Linkage category for a 1989 Cougar, XR-7 or otherwise. I was looking for it earlier and still don't see it...

Edit: Nevermind....searched under 1990 instead of 1989 and found it. Don't understand why they do that
 
Will quick lube places know enough to put in the right additive when changing diff fluid - or should I pick up the additive myself at Ford and TELL them to put it in?

Ask and see if they look you in the eye when they respond. Maybe they'll allow BYOA, if you tip 'em, but they work on the clock, and in my experience have a habit of overfilling, so they can charge for more product, then putting the plug in before the level can drop to where it's supposed to be, leaving you with leaks later as the seals get overwhelmed. I wouldn't let them near this job if it were my car.

I would put the additive in first, so the whole bottle goes in (on the assumption the diff hasn't ever seen luv), then top off with 80W-90, then let it drain to the bottom of the hole while on level ground. I understand it's a pain, tho ;) Ideally, given the age of the car and holes in it's history, you'd want to drain and fill, of course.

Hit up some of our vendors for cable & bushing (w/clip), and/or use the want ads here.

spinningwheels-sc http://spinningwheels-sc.com - Victor/Diane
supercoupeperformance - https://www.supercoupeperformance.com Bill
tbscshop http://www.tbscshop.com
 
So great to have so much input, thanks guys.
.
.
I haven't been able to spend a ton of time on it the last couple of days, but I did a bunch of testing....drive, stop, adjust, drive, stop, adjust...and I was able to get it shifting up through all 4 gears at what I would call 'normal' shift points. However, the downshifting wasn't even close to right and I'm 99% sure it's because I don't have the right bushing on the throttle lever where the TV cable connects.

Thanks again for the help. I'm glad there's still lots of guys on here. Can't wait to start working on my SC in the spring and do some fun things to it vs just trying to get this Cat driveable!
Its not the bushing. The setting for the AOD TV cable is not that sensitive. I drove for 10 years with one attached with a twist-tie. :eek: and it worked perfectly fine. If its driveable, just drive it until it stops shifting.. BTW, AOD downshifts are just bad all over.. you need to almost floor it to get a downshift, so don't sweat that part. One tip: Try driving in "D" in town if you're generally driving 50 or slower. You'll be much happier. :D
 
Good afternoon


I believe the overall shifting issue could be reduced with the addition of @Lube Gard Red to the transmission fill. It is not transmission fix in a can (or bottle in this case) but if the valve body has varnish causing valves and pistons to stick this product address the issue. I would do a complete drain (including the torque converter), inspect and filter change with the Lube Gard additive. Do search on the reviews.


http://www.lubegard.com/SearchByCat...GARD+Automatic+Transmission+Fluid+Protectant#
 
Good afternoon


I believe the overall shifting issue could be reduced with the addition of @Lube Gard Red to the transmission fill. It is not transmission fix in a can (or bottle in this case) but if the valve body has varnish causing valves and pistons to stick this product address the issue. I would do a complete drain (including the torque converter), inspect and filter change with the Lube Gard additive. Do search on the reviews.


http://www.lubegard.com/SearchByCat...GARD+Automatic+Transmission+Fluid+Protectant#


Thanks for that....now I won't pull my hair out trying to get the downshifts perfect. I got a new bushing today but didn't get to working on the car. Tomorrow. I also thought the TV adjustment was super sensitive for something that attaches to a cheap plastic bushing, but there WERE very noticeable differences in the shift points with only a one or two notch adjustment. As you say though, downshifts seemed less affected.

I also wondered about valves being sticky, especially if it was sitting without the proper amount of fluid in it. I'll definitely change the filter and fluid and put some additive in it, thanks.

Question: How does one drain the fluid out of the torque converter without removing the transmission from the car? Hope that isn't a stupid question...it's been a while since I had a transmission out of a car, and from what I remember the only way to get fluid in or out of the converter was through the opening for the input shaft?
 
How does one drain the fluid out of the torque converter


The TC should have a small drain plug, accessed thru the rubber cover lower front of the housing - spin the flywheel to locate. Add the diff fluid while the car is off the ground and you're waiting for the trans/TC to drain, unless it's still too cold to be underneath, as you said before. Let's hope that much fluid change doesn't cause issues.
 
Its not the bushing. The setting for the AOD TV cable is not that sensitive. I drove for 10 years with one attached with a twist-tie. :eek: and it worked perfectly fine. If its driveable, just drive it until it stops shifting.. BTW, AOD downshifts are just bad all over.. you need to almost floor it to get a downshift, so don't sweat that part. One tip: Try driving in "D" in town if you're generally driving 50 or slower. You'll be much happier. :D

Got it...I've noticed that before too...that downshifts for something like passing requires you to almost floor it. The downshifts I was more concerned with were at slow speed i.e. slowing down then trying to accelerate but it's still in 3rd, or even 2nd if you're almost at a stop. Is THIS the kind of thing that will bake the transmission? I'm never been clear on exactly what condition a disconnected TV cable causes that would bake the trans.
 
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