# 91 XE auto transmission problem



## ufa (Oct 10, 2004)

I'm not sure if this is the right forum to post in, so spare me.

I purchased a used 91 XE a month ago. Had muffler changed, slight leak infront of the catalytic converter was sealed. The engine has 112k KM on it ( 69,593 miles ) and is in really good condition and noise levels. I drove for 2000km already including highway running.

The car had good torque. Upon purchase I found out that shifting from first gear to second would happen within 0-15km on the speedometer and often a hard shift/thud, and if I did a hard accelaration there would be a sudden kickback. I showed it to a mechanic friend and he said if it wasn't showing any other problems I can just ignore the thud and it should be okay. I had assume at the time that perhaps it was a ECU setting issue where the engine was revving up and shifting too quickly, before the car was upto speed.
If I drove the car in 1 or 2 gears during tests, no such _thud_ would occur. Reverse was fine as well.

Fast forward to yesterday night, and I stopped hard at a red light, and doing a right turn, then tried to accelrate and the car would barely move. It felt like I was pushing another heavy car infront of me. Or how driving would feel with the braked pressed, or perhaps handbrake left on. If I pressed the accelerator pedal hard enough, the engine rev's up and then all of a sudden it'd start moving with the kickback, almost as if it was skipping the first gear completely.

I drove it back home in this condition, assuming that perhaps the brakepads had gotten stuck. Took it to a mechanic, he took it out for a drive and said it's a transmission problem and he' replaced the transmission fluid ( which was clear and almost new ) with new fluid and some transmission treatment that he said might help fix the gear shifting, and then he told me to drive it around for a few days to see if I have any improvements. Or else I may need to change my transmission.

So far, I have noticed no improvements driving around today. I still have to rev up the engine quite high before the car starts moving. The mechanic said I have to do this gradually rather than hard pressing for accelaration. I must admit that the car still does go up to around 80km/h (I tested it twice , didn't want to go any faster incase I break something) , and I hear no such kickback or thud as previously experienced -- it's a smooooooth speeding up and speeding down session if I don't use brakes, but requires a long strip of road. It's tough driving around because everytime I stop, someone behind me gets really irritated at my speed pickup and starts honking. I even had to turn on my hazard light once so they'd go around me. I have tested this in both D, 1, 2, and Reverse. All of them work, but takes time and revved up engine before it starts moving. I assume if it's working in 1 then that means first gear is working?

Searching on the forums it seemed some people have had problems with the governor as noted ( http://autorepair.about.com/library/faqs/bl585d.htm ) and also on this forum. I don't know if it's related. The mechanic I showed it to today mentioned no such thing.. I am planning on taking it to another mechanic tomorrow. 

I'd like any advice from anybody that knows or could offer some insight into this problem. I am not much a car expert but I guess if I should own a sentra better start learning to love what comes with it


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## Catman (May 21, 2004)

Welcome ufa! Your problem is a new one to me. If going to the other mechanic does not help, or no one here has a solution to your problem, you may consider going to a dealership for diagnosis. They may have to run some tests, to find what is wrong with the transmission. Unfortunately, dealerships have the experience specific to your vehicle and the test equipment needed. I have not had good luck with chain transmission shops. My experience is they tried to do repairs I did not need and were deceptive. Another option would be a reputable independent shop that knows your vehicle, but the dealership would be my first choice for diagnosis. Good luck!


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## JerodKing (Jun 5, 2004)

I'm pretty sure when I was first looking at Sentras, one thing consumer guide said for problems in automatics is that they have a really hard shift if you don't use what I think is called Nissanmatic C transmission fluid. I would find out if thats what the mechanic used, and if not, go to the dealer and pick up a few quarts of that and change your tranny fluid again.


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## ufa (Oct 10, 2004)

Thank you both. 

I haven't had time to take it to another mechanic, and tomorrow is still a holiday here. So perhaps tuesday. I'll also keep the nissan dealership in mind.

I don't think it's the fluid right now.. I have a feeling it might be a worn out gear, the governor. But I hope a proper mechanic would be able to tell by driving. It's sad that most mechanics just take guesses at what could be wrong and offer to replace entire parts thus more labor hours.

Ah well, cest la vie.

I'll keep you posted.


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## Catman (May 21, 2004)

JerodKing said:


> I'm pretty sure when I was first looking at Sentras, one thing consumer guide said for problems in automatics is that they have a really hard shift if you don't use what I think is called Nissanmatic C transmission fluid. I would find out if thats what the mechanic used, and if not, go to the dealer and pick up a few quarts of that and change your tranny fluid again.


I have used Dexron III since I purchased mine used 7 years ago. No transmission problems, works like new with 168,000 miles.


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## ufa (Oct 10, 2004)

Hmm

I found a few posts that reflect on pretty much the exact same problem I am having. Except in my case I did not see any chipped metal pieces while doing tranny fluid replacement. 

http://www.nissanforums.com/showthread.php?t=66919
http://www.nissanforums.com/showthread.php?t=53196
http://www.nissanforums.com/showthread.php?t=52962
http://www.nissanforums.com/showthread.php?t=62828
http://www.nissanforums.com/showthread.php?t=49794
http://www.nissanforums.com/showthread.php?t=62264

I assume since my nissan is a 91, it probably has a governor with nylon/plastic head? perhaps worn out. Should I try to replace this on my own? Or is it better to see a mechanic? 

Also, are there any online dealerships that sell this? Or perhaps there is a part number I can request to dealer? I don't have a FSM so I don't know what the part number is.

Paying 100 bucks for them to provide a 'special tranny treatment' was probably stupid for me.


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## ufa (Oct 10, 2004)

I called nissan dealership.

They said I have to buy FOUR parts , they won't sell me just the governor gear. And that it'd cost around 325$ + 160$ in labour +tax! 

Part number 31859 31x10

Anyone know where else I can just get the gear itself? I can't find it anywhere online


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## ufa (Oct 10, 2004)

After trying 6 places that wouldn't sell me the gear by itself, and all wanted to sell the entire shaft, 2 even told me that the 'gear' wasn't replacable..

I found http://www.courtesyparts.com/ -- $33 + $18 shipping.

Gotta wait about 2 weeks.


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## ufa (Oct 10, 2004)

After trying to get the 'cap' open I've run into a dilemma.
I'm requesting help from anyone that's done it before.. or knows how to.

I've removed the airducts and cleaned the cap area with wd-40 and towel. It's not too clean still. I'm curious whether any dirt might get inside once I open it.

Also, to open this lid or snap cap, I am not sure which way to push or pull.. or which slot to hinge the screwdriver head into. I also don't know whether it'd get ruined that I may not be able to put it back properly.. so I want to do this as smoothly as possible. I don't want this to be leaking later.

I took some pictures, please look at these and let me know..
Thanks

More pictures at 

UPDATED LINK : http://snickers.org/~vortexer/sentra_b13/gov_gear/


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## Catman (May 21, 2004)

I looked at Alldata, no useful info. Only listed the cap and governor. No instructions. You said you saw a few posts with pretty much the same problem. Maybe you could send a personal message to those members who posted that they repaired the same part. (In case they do not read your current post). Maybe an FSM would have more detailed instructions.


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## ufa (Oct 10, 2004)

Catman said:


> I looked at Alldata, no useful info. Only listed the cap and governor. No instructions. You said you saw a few posts with pretty much the same problem. Maybe you could send a personal message to those members who posted that they repaired the same part. (In case they do not read your current post). Maybe an FSM would have more detailed instructions.


I've tried messaging a couple, but looks like they came by and left the boards once problem went away.. and I do not have access to an FSM =(


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## Catman (May 21, 2004)

FSM is a Factory Service Manual. Even then, it may just say to remove the cover. May not give tips is it is stuck.


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## lshadoff (Nov 26, 2002)

Here's the procedure from the B14 FSM (should be the same as yours). It looks like they are using a screwdriver blade to lever the snap ring out.










Lew


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## Catman (May 21, 2004)

Maybe you could email this guy for details on the cap removal. He has a nice picture of replacing the gear:

http://autorepair.about.com/library/faqs/bl922d.htm


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## ufa (Oct 10, 2004)

After much trial and error and a heavily battered cap, I managed to take it out ..upon realizing that there were two rings holding the cap. One of these rings seemed very much like part of the transmission , so I didn't even assume that it could be separated.. until I started bending the cap slightly.

Turns out one of the rings -- you need to bend in somewhere in two spots and drag it out -- and the other, which doesn't complete a full circle, you need to grab one end and drag it out using a nose pliers.

Anyway.. here's what the gear looks like:

UPDATED LINK : http://snickers.org/~vortexer/sentra_b13/gov_gear/  

When I rubbed it using my fingers I had a few plastic chips come off.

I'm hoping replacing this once I recieve the new part fixes the problem and there's no left over chipped plastic inside the tranny -- or worse yet, a messed up tranny I already have and am not aware of it..


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## Catman (May 21, 2004)

Glad to see the progress. Hope it fixes the problem. Regarding your concern about chips in the transmission, you could drain and refill with new fluid. Not sure what you meant by this:



> Paying 100 bucks for them to provide a 'special tranny treatment' was probably stupid for me.


I am not sure if you had the tranny flushed by a machine hooked to the cooler hose. If you did, I would think it flushed things out. After I had mine done, I dropped the pan after 30,000 miles. Very clean, and filter screen was very clean. It does not look like a lot of material came of the gear, so hopefully it would just be caught in the filter screen. Of course some more gear material may have come off since that transmission service. Maybe just drain and refill with Dex lll. The shop that flushed mine used Coastal brand of ATF (cheap stuff). Worked just fine. Or, if you are ambitious drop the pan and clean it out. I would just not mess with the filter screen. There is one bolt holding the valve body and the filter, once removed, it is hard to replace the nut. Don't over torque the pan bolts, I did and snapped one off. :thumbdwn: That being said, just draining and refilling may be enough. When I do it I like to check fluid level before removal, and measure what comes out. Gives a good reference for what is needed for refill. It is like changing the oil, much easier than what you have done so far.


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## ufa (Oct 10, 2004)

I got the new part but it doesn't match, nor is it metallic.
I called courtesy parts and they say it may be the 'updated version' .. or that I may have to get the entire shaft.

Courtesy Nissan's part number for the shaft is also different: 31859 - 31x18

Here is an image .. It's slightly larger, almost 1 cm, and difference in thread curls. I'm wondering if I should try it, or if I should saw it off and try it.. or .. ahh I don't know.

help!

http://snickers.org/~vortexer/sentra_b13/gov_gear/gears.jpg


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## lshadoff (Nov 26, 2002)

It may not work. The worm gear inside the trans is a different pitch, and they might not mesh properly. However, if the part was cheap, it's worth a try.

Lew


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## ufa (Oct 10, 2004)

I'm returning the part. It doesn't go in, I've tried. 
Going to just get the entire governor shaft , enough hassles for me already with this =\


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## ufa (Oct 10, 2004)

*Got the gear replaced.. but..*

So finally the gear arrived, cost me around $200usd+taxation including the shaft/springs to get to canada. Going to return the wrong gear they sent soon.

*ANYONE READING THIS FORUM REGARDING THE GOV GEAR -- ALL POSTS BELOW RELATE TO A DIFFERENT PROBLEM. THE GOVERNOR GEAR GEAR HARDSHIFT ISSUE IS RESOLVED.*

http://snickers.org/~vortexer/sentra_b13/gov_gear/

It indeed is Metal, and seemed fairly solid.
This morning after having my car off for 3 weeks, I finally replaced it, hooked everything back up on the engine air intakes, and then closed the hood. I took the opportunity to fix the blower motoro resistor as well, which works perfectly now.

However, problems still exist. I took the car out for a drive and at the very first move ( reverse ) I heard a clunk, and then the car started to move. And I realized there is still lack of initial power. If I place the car in drive, it won't go forward unless I start revving up. If I am going slightly uphill, and stop at a red light, car starts going backwards unless I press on the breaks or keep revving up slightly.
However, the gear shifting works fine now, I can feel and hear the gears moving up 1>2>3.. missed #4 .. not sure if it went that high, but I took it on the highway and got to 120km/h .. and drove around almost 20 km. I thought maybe it'll fix things if I drive more. It seems when I start driving, as soon as the car is upto speed around 20km/h , everything else is smooth from there on end.

I've been doing some thinking on what could be the problem. From the sentra.net site, it seems to be transmission fluid replacement talk. Now, the tranny fluid was replaced by the 'mechanic' who charged me 100 bucks for fluid flush and adding an additive into the mix, that was supposed to fix the hard shifts. I do not know the brand of it, but I recall him holding a blowing heat gun to heat up the bottle just so the additive would pour out into the funnel.. it was sticky. He said I was to drive the car around for 3-4 days and not rev it too much, and it might fix the no shifting problem. Obviously he didn't know about the governer gear issue at all.. and I had to fix it myself, and now I feel that tranny fluid change was unnecessary, and possibly worse off for my car. 

The transmission fluid currently in the car is much lighter/thinner in texture than what I had before, it feels very thin when wiping off. It also isn't as colorful. So I'm not sure of the additive was supposed to thin my fluid. Also, I do not know if the winter weather has anything to do with it. On the sentra.net site it mentioned Nissanmatic D, And Redline or Motul. I'm not sure if Redline and Motul are for manual transmissions only. Does anyone have any experience with a problem as such, and know where to go from here? Also, would the transmission fluid filter require cleaning as well? Has anyone does this?


I'm also curious if the problem could be cable adjustments somewhere, perhaps idle speed settings.. or even the flywheel. It just doesn't want to move when idling/stopped.. I hear acceleration and engine sound though -- until enough goes through.. and then moves.

Any help or advice is appreciated.
Thank you guys so much. Atleast my shifting issue is fixed for now!


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## Catman (May 21, 2004)

> The transmission fluid currently in the car is much lighter/thinner in texture than what I had before, it feels very thin when wiping off.


New fluid will be lighter in color. Hard to read on the dipstick. I lay it on a white paper towel to see the level after changing. This is normal. When it gets cold outside, the fluid will thicken. During warm weather, it looks very thin. I don't know what the additive was supposed to do, but my concern would be it is not having a beneficial effect. 

First, you may have done this, but make sure to check the fluid level when the car is warm and after moving the shifter through the gears. The owner’s manual should have the procedure, if I am not mistaken. I have found some shops put too much or too little fluid in during servicing.

Second, it may be a good idea to change/drain the fluid and drop the pan following the precautions I posted earlier. That is the only way you will know the condition of the filter, and you may find some of the disintegrated gear in the pan or filter. Based on the additive in the transmission, it may be a good idea to replace the fluid a second time after a short interval of driving (a few days) using the drain plug. That will make it closer to 3/4 or more new fluid. This is what I did on my Saturn to flush an additive that was not good to leave in a long time. Don't know about Nissanmatic D, Redline, or Motul. I just know inexpensive Dex lll has worked fine in my Sentra. In my Saturn, I have switched to Mobil 1 Dex. lll. Definitely smoother shifting. But the Sentra is old and I am on a budget. 

Regarding the thud going into reverse or having to rev the engine, that is sounding more like a valve body problem. Those symptoms sound similar to a problem I had in my Saturn that had a sticky valve body. Had to rev it to go into gear, and it would thud into reverse. Would drive fine through the gears. I don't know if there is a fix for a Sentra without replacing the valve body. I am sure a dealership would have the equipment and know how to test the valve body/transmission operation, but for a price. If changing the fluid does not help, and you can't get things figured out here, then it may be worth looking into a valve body problem. 

Here is a possible explanation?

A/T - Slips, Improper Operation/Shifting
Reference: TECHNICAL BULLETIN NTB94-OO6a
Date: November 29, 1994 
1991-93 SENTRA (B13) IMPROPER OPERATION OF F03A AUTOMATIC TRANSMISSION
APPLIED MODELS
1991-93 Sentra (B13) with FO3A (4 speed A/T) 
APPLIED C/M DATE
February 1993 
SERVICE INFORMATION
This bulletin applies if a 1991-93 Sentra exhibits one or more of the following symptoms:
^	Automatic transmission downshifts from 3rd gear to 2nd gear and will not upshift back to 3rd gear. 
^	Automatic transmission will not upshift to 3rd gear on normal acceleration. 

^	Automatic transmission will not upshift from 3rd gear to 4th gear. Shift shock from "N" to "D". 
^	Automatic transmission slips, poor acceleration. 
NOTE : Automatic transmission operation is normal until engine reaches operating temperature of 95°C (180°F). 
SERVICE PROCEDURE
Some of these symptoms may be caused by a burnt High Clutch or a sticking Control Valve Assembly. Debris from the burnt High Clutch may have gotten into the Control Valve Assembly, causing it to stick. The shape of the oil feed hole on the oil pump housing has been modified, allowing oil to enter more easily. This improves oil flow and lubrication, preventing a burnt High Clutch.
1.	Replace the damaged High Clutch as an Assembly (refer to the appropriate Parts Microfiche for the correct part number with respect to vehicle production date). 
2.	When repairing the automatic transmission on a 1991-93 Sentra (B13), the Control Valve Body should be cleaned and thoroughly inspected for wear on individual valves and Control Valve Body bores. If wear is noted, repair or replace as necessary.


You have really been through alot with this car. I hope it works out for you!


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## ufa (Oct 10, 2004)

I changed the fluid today to Drex III ATF .. 
I have a feeling I may have put too much back in. More than I took out. Almost 5 Litres.. not sure if that's too much.

One thing I *did* notice before the transmission fluid change. This morning in the cold, I checked the previous fluid level, and It showed the full amount as it would when hot. I also noticed, as soon as I started it up, it moved without effort on reverse/first gear.. but about a minute later when the car was slightly warmer the problem started happening again. So yes, it is still happening.

I jacked up the front of the car on two stands and tried to see if it was perhaps the car's weight not allowing the wheels to move on drive. It seems that is not the case either, even free moving the wheels would not move in drive -- until revved up for about 5 seconds with high accelaration.

I noticed the throttle valve controller.. the cable from the accelarator, and the other one ( not sure where it goes to ).. both are slightly lose.. Not sure if that has an effect. ie, you can press the cable down with your thumb in the exposed part about a cm without any raise in accelaration. 
The actual part that goes towards the valve below the engine mounting bracket doesn't seem to have much tension, it's just pulled in all the way. So, I'm not sure if this affects idle speed, or speed in drive.

I'm not sure if I should try and tune this myself or find and actual nissan shop to take it to. Also, I do not have a tachometer that I can plug into to check the actual idle speeds and such. Haynes manual isn't too informative.

Catman, you also mentioned the Idle Air Control Valve Unit in a few other posts.. Could that be a problem, perhaps?

I just refuse to believe it could be really a transmission issue.. heh. When I bought the car everything was working fine, except the slight thud going from first to second too quick. Not sure if that has to do with throttle control valve as well. But atleast the shifting happens smoothly now.

If nothing else, I'm learning a lot about how cars operate from this experience.


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## Catman (May 21, 2004)

> Catman, you also mentioned the Idle Air Control Valve Unit in a few other posts.. Could that be a problem, perhaps?


I read, and re-read you the post of your current symptoms. I did not mention the Idle Air Control Valve Unit since I could not tell if you were having idle problems or transmission problems. Just didn't want to add too many variables. Before cleaning the IACVU I would push on the gas and the car would not want to go. It did almost seem like the transmission was not working properly. Now I know that is not true. The difference is that I never had problems going into gear, loud thuds, or problems shifting through the gears. Only was slow to shift into overdrive on a cold day. Needed to warm up a bit. It would not hurt to clean the IACVU spring. It is inexpensive to clean. But, I don't know if it would resolve your issue. I guess there is only one way of finding out.

The TSB I posted said: 



> Automatic transmission operation is normal until engine reaches operating temperature of 95°C (180°F


I had problems with valve body on my Saturn transmission. The problem was worse when warm. Not being a mechanic, I am guessing with my limited experience. But it may be good to consider the valve body in the transmission as a possible cause.

When I change fluid, I like to check it before removal when hot, then I fill the empty transmission fluid bottles to determine how much came out. I think mine is at the level on the dipstick you described. May be a little overfilled, but do not notice problems.



> If nothing else, I'm learning a lot about how cars operate from this experience.


Yes you are. Keep up the good work!


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## ufa (Oct 10, 2004)

After much much work and crap done on the car... AAMCO transmission rebuild was the only option. Apparently the hydrolic pump was damaged inside, the torque converted needed changed, as well as some thing else.. I forget the name of.
Basically I paid 2x the price of the car's oriiginal purchase price to get this fixed.. and even then, with reconditioned parts, so I have a 40k km warranty, or 18months.

Now I think there are more problems.. ( the initial problems have all disappeared now since the rebuilt and the car drives much better .. however ) -- the actual shift stick is somewhat loose, and i thinkt here may be mount problems -- hearing a clunk going from fwd to rev shift 
and also weird irregular whining noise as soon as you put the car from neutral to fwd/rev.. which slowly get's faster and faster as you drive at higher speeds, then starts to get inaudible. I'm going for a follow upa gain to aamco in two weeks or so. Just thought I'd give you folks an update.


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## Nau (Dec 19, 2004)

Catman said:


> I would just not mess with the filter screen. There is one bolt holding the valve body and the filter, once removed, it is hard to replace the nut.


Hey, That's what I did.
Never figured out how to put that bolt on and just drove as it is, with one bolt missing :dumbass: It drives just as before though...

If you know how to put the bolt back on, please tell me!

(I started changing filter in hope to get gid of the kick when the car shifts from 1st to 2nd - it did not help)

What's bad in driving without that bold? (I drive it like that for two years now  )

Thanks!


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## Catman (May 21, 2004)

Nau said:


> What's bad in driving without that bold? (I drive it like that for two years now  )Thanks!


According to this guy, there is no problem:

http://autorepair.about.com/library/faqs/bl633.htm

Plus, you have gone two years. As long as you keep up on draining/replacing the fluid, you will probably be OK. What else can you do?


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## Nau (Dec 19, 2004)

Catman said:


> According to this guy, there is no problem:
> 
> http://autorepair.about.com/library/faqs/bl633.htm
> 
> Plus, you have gone two years. As long as you keep up on draining/replacing the fluid, you will probably be OK. What else can you do?


Oh boy  No way my fingers will get inthere. What happens to the nut then?
It just stays there forever (I hope it doesn't get loose flying around in my tranny!)

I just joined this forum, what a wonderful place! I wish I knew 'bout it 3 years ago when I started learning my Nissan car work the hard way 

Now finally I gotta find why I get this nasty kick from 1st to 2nd shift

Thanks, man!


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## jharris1 (Mar 13, 2004)

Wow, my car must be an exception. I think I got my torment driving the 87 Sentra with the neck snapping shift from 1-2, the slip from 2-3, and what seemed like a brief stint in nuetral when I could have sworn I put it in reverse. Now, my 93 Sentra tranny shifts strong and hits all of its shifts without a kick or a clunk. The only gripe I have is that it feels like it shifts into overdrive too early. I'm sorry to hear Ufa about the unfortunate tranny problems. Especially the fact that you had to take it to Aamco, and it sounds like they did a shoddy job. I wouldnt trust Aamco as far as I could throw 'em, but hey sometimes you gotta break down and shell out the $$ unless you have some tools, time, and patience to remove a tranny from an older car and risk shearing some bolts and getting a citation for cussing up a storm. 

Seems like removing an auto tranny would be a little harder than removing a manual. Plus the auto is heavier. Bench pressing the auto out cannot be fun. I was involved in removing a manual and it took about 1hr to remove with the proper tools. At any rate, good luck Ufa. Take the car back to Aamco and force them to fix some of your problems. Some of it might be their fault (if not ALL)


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## Catman (May 21, 2004)

jharris1 may be right about Aamco. The one time I went there the manager complained of how hard it was to keep trained personnel. Unfortunately, your transmission may have been part of their training. I really wish the best for you. It is a real pain to have so many problems then have to go back to Aamco.


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## tommypslowdown (Oct 24, 2014)

Same problem. changed gov gear. all is well. got part from trans shop. 20$!!


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