"New to site" 92' tranny or electrical issue?

[derangedone]

Hi guys, looks like a real nice site here! I just purchased a 92' STX 4x4 from a friend of mine for cheap but the truck has some issues. It hasn't done it to me yet but it will sometimes stick into 1st gear and not shift and I notice only 3 shifts and the torque converter is not locking, where would you guys start? I read a little about checking a wire for voltage and see if the computer is telling the converter to lock or not. I heard a lot of things can make them not work, I know one thing the factory tach does not work properly! could this have anything to do with it? The tranny has not been serviced in a long time but it is not slipping it just gets stuck in first sometimes after warmed up. what do you guys think could be the most likely candidate? trans solenoid, governor, or sensor "elec" ? thanks

 

[derangedone]

Hi is it pin 80 on the PCM that I should check for 12 volts when driving down a highway to see if the PCM is trying to lock the converter? Does anyone know what color the wire is down by the tranny? I have read this could be so many things! Speed sensor, temp sensor, anyone know if my crazy acting tach might have anything to do with it? Or what might be wrong with tack? It likes to stay around 3,000 rpm! Drops to zero with the ign on but goes to 3,000 when idling. May just be the tranny but don't want to replace it and have it doin the same thing, also the 4x4 is not engaging I believe it to be dirty terminals under that cover or faulty motor. All those wires that lead to that cover are for the 4x4 transfer case motor only arnt they or do they go thru the motor and control the solinoids also? I was going to take that cover off and clean the terminals last night but I can't find my tamper proof bits dang it! Thanks guys

 

[jhammel85]

3 shifts is right if you think about it, since you start in 1st.

As far as the problem on getting stuck in 1st, Its the governor. They bind up and it's a fairly common problem. One way to fix it is to clean / replace and install a 35mm Weight. It's easier to get to then you think. See this link (note that you really don't HAVE to remove that transmission housing. I didn't.
http://www.explorerforum.com/forums/showthread.php?t=155582

Here's a breakdown:

- Drop drive shaft on one side, Skid Plate and Trans Crossmember.

- Remove linkage for Transfercase (if it's manual) at the transfer case via a 13mm bolt, IIRC. If it's electric, remove all connectors and mark as needed.

- Unbolt speedo gear cable and any other electronic plugs you have on your TC and mark accordingly.

- Support TC on jackstands and a jack before unbolting. Remove 5 TC bolts.

- Use a pry bar to carefully break seal and then do your best to drop the TC down or get a buddy to help you hold it steady as you raise it up to remove the stands and drop it down.

- Once that's out of the way, You can look inside and see the gov and it's two bolts. When you remove the bolts, theres a chance of the gov falling apart on you and cause you to lose some pieces. Undo the bottom bolt and hold it steady as you take out the upper bolt. Be weary of letting it fall.

- Fully inspect and clean with brake clean and a crocus cloth. Make sure you get the valve out of there and that it's moving freely under its own weight.

Then just put it all back together and torque as needed. Black RTV for the TC to Trans Gasket and red locktite for the bolts in the drive train. Then refill the transmission with fluid since you lost some when you pryed the TC and Trans apart. Make sure to use Dex III / Mercon or Mercon V (I used V)

For what it's worth, Here is a link to guys who sell the govs. If you can remove the governor 1st and then order one, allowing down time, I'd look into buying a new (technically used) governor. Buy the 35mm weight regardless of you're using the old gov or buying a new one. For eight bucks, it'll overcome any binding that may happen in the future.

http://www.wittrans.com/showfilter.aspx?Category=717&Section=119

 

[jhammel85]

I just saw the other problems too..I'll have to think about those a bit!

 

[Surrey]

http://www.therangerstation.com/tech_library/lockup_switch.shtml

This talks about pin 53 for installing a lock-up switch. So thats probably the one you need to check?

 

[derangedone]

Thanks Jhammel and Surrey for the advice! I will check out that governor if I can first get a grip on the other issues, I don't want to sink a bunch of $$$ into this tranny unless I think I can fix it cheaply if not I will get one out of a salvage yard before I put to much money in this one. I think I read on the Explorations site that I should feel what feels like 5 shifts one of them being the torque converter locking up? I only feel what feels like 3 shifts, I don't think the trans is shifting into overdrive and I know the torque converter is not locking! I would like to figure out if this is a solinoid issue inside the tranny or a electrical problem or bad sensor in the engine? If it is all trans issues I may just get another tranny if not I will be willing to battle this one, if it is just the governor and solinoids even I may give it a shot but.... My mechanical skills are good but I know transmissions are sensitive and I really don't enjoy working on them but will if I think I can get somewhere on it cheaply. Thanks again guys!

 

[derangedone]

Hey Jhammel or anyone, I noticed on that thread they said usually the governor is to blame with the tranny sticking into 1st gear when the engine is cold. This truck has NEVER stuck in first with the engine cold it has always been after driving it for awhile, could this still sound governor related? The truck has not done this to me yet but I have driven it very little " only home". I am going to try to drive it tonight with my old diagnostic computer hooked up and ohm meter and see if the computer is even making a attempt to lock the converter, and see if the engine is open and closed loop both. I am also going to check and see if cruise control operates, someone said on Explorations that if the speed sensor is bad the computer won't lock the converter and may not put tranny in OD.

 

[jhammel85]

No problem! When you are running at about 50 or 60, are you somewhere between 1500 to 2100 rpm?

 

[derangedone]

Hi well here are my results on wire #53 on PCM "purple wire with yellow stripe" with the truck running and driving the voltage was at 12.40V once I get into last gear it was .57V does this sound right? Is the computer working properly? If so it must be the tranny, I also tried the switch to lock it up and it failed to lock, so you guys think the solinoid is shot?

 

[derangedone]

Can't tell jhammel85 the tach is not working properly, it goes to 3,000 rpm at idle. I think rpm is higher than 1500

 

[derangedone]

still no go

Hi guys I have been working on the truck trying to get it going so far I removed the valve body, installed superior shift kit, replaced tcc solenoid and the 3-4 solenoid and the truck is still doing the same thing. Someone has mentioned the 50 mph test which is driving down the road at 50 and lightly put foot on the brake pedal without letting go of the gas pedel and the rpm's did rise a little! So I think the torque converter is at least soft locking but not all the way. Anyways I read a lot of electrical issues will cause tcc lockup difficult " but the computer was still sending 12.4 volts to solenoid" however one thing crazy on this truck I cant figure out is the BATERY LIGHT stays on on this truck all the time and has been on for quite some time I believe, so I am wondering if the tcc problem might have something to do with this? The alternator is good though and keeps the battery up. I checked it with my battery charger which has a alternator test and it tested ok. I went to autozone anyway and bought a new one to try and the light stayed on! Does anyone know what might be causing this and where and what wires to look for? Also the tachometer is not working properly when at idle the tach goes over 3,000 anyone have any suggestions for this? I cant help but think the tranny is not working properly because of elec issues. Thanks

 

[derangedone]

Well I guess I was wrong, I talked to my friend about the light and he said it was never on before, I thought it was. I started the truck today and the light went off, I think it may have been my test tools on the ecm possibly causing the light possibly I don't know how but that is all I did before I started the truck to take it for a drive. However I still have the tranny issue, I could just swear that I feel 4 shifts one probably the torque converter doing something but something is still not right, one thing there is no difference when I shift from OD to D rpm's stay the same so I don't know if the torque converter is not locking all the way or the tranny is just not shifting into 4th? when I let off the gas the rpms drop to idle and if I hit the gas again it jerks cause the engine is trying to catch back up and if I change from D to OD nothing happens. What do you guys think?