Transmission Missing Gears

[Meashii]

I have a '93 MX-3 GS automatic, I bought it with the tranny already missing gears. The Hold light is blinking, and it seems to skip from 1st to 3rd gear and wont shift up to 4th. Either in never goes in 2nd or it very quickly in and then out to 3rd. I've tried shifling into 2nd (S) with the shifter, and it still seem to just go into 3rd. Reverse works fine, and the transmission fluid is alittle dark but doesn't smell burnt really.

Where should I start to fix it? Pull the codes? Take the tranny to a shop to have a rebuild? Or should I try replacing the fluid and filter first?

I figure I could waste my time and money since I'm not sure what to try first. Any feedback probably will be helpful.

[shameem]

Well you can start by pulling codes -
http://www.mx-3.com/phpBB3/viewtopic.php?f=30&t=66158" onclick="window.open(this.href);return false;

A fluid/filter change and adding a transmission cooler would be a good idea.

[Meashii]

Yes, I've thought of putting in a transmission cooling system. Because I've read that heat is often the cause of transmission damage.

I was told by a mechanic around where I live (though I live out in the middle of nowhere), that if I was missing any gears at all that if I tried replacing the fluid and filter that I mostlikely will loose all the gears. Which doesn't make much since to me, but I don't know that much about automatic transmission.

Thanks for your advice. I'll try pulling the codes myself again today, and see what it tells me.

[Meashii]

Ok, I've pulled the codes. There are two codes 55(pulse generator), and 62(solenoid valve 3-4). I've been searching around the net trying to find more about what a pulse generator and the solenoid valve actually do and how to go about fixing them. Been searching for a hour or so, and have found nothing so far.

[shameem]

The pulse generator is a sensor mounted on top of the transmission -
http://www.mx-3.com/manuals/showimg.php ... _K-153.gif" onclick="window.open(this.href);return false;
http://www.mx-3.com/manuals/showimg.php ... _K-104.gif" onclick="window.open(this.href);return false;

The solenoid is inside the valve body - you have to drop the pan to get the valve body out and then replace it - you can test the solenoid from outside though -
http://www.mx-3.com/manuals/showimg.php ... _K-156.gif" onclick="window.open(this.href);return false;
http://www.mx-3.com/manuals/showimg.php ... _K-112.gif" onclick="window.open(this.href);return false;

[Meashii]

Ok, I've found that the wires to the pulse generator had been cut. I've sliced the possitive wires together and hooked the negative under a bolt on the frame close by. I checked the codes from the transmission again and the only code 62 is displayed. But, I tried to test the circuits for it, and got no resistance on either on the circuits. Still, the code is on displayed.

As for the solenoid valves. Valve A checks out good, the rest faild. Solenoid valve B read at 1 ohm. Solenoid valves C and D have 0 ohm's of resistance. I don't know what this means. I don't know where the EC-AT Unit is to test it. I'm gonna try and find out where that is so I can test that. As for the solenoid valves I presume that they need to be replaced......?

[shameem]

The EC-AT control unit is located inside the car below the center console behind the radio.

http://www.mx-3.com/manuals/showimg.php ... _K-002.gif" onclick="window.open(this.href);return false;

You can try to take the valve body apart and try to clean it and replace the solenoids - it is located inside the transmission -
http://www.mx-3.com/manuals/showimg.php ... _K-156.gif" onclick="window.open(this.href);return false;
http://www.mx-3.com/manuals/showimg.php ... _K-176.gif" onclick="window.open(this.href);return false;
http://www.mx-3.com/manuals/showimg.php ... _K-226.gif" onclick="window.open(this.href);return false;