hi!
I have '92 929 USA modell and I've the folloving failure. if I start to drive the transmission is shifting 1-2-3 normally, but I have'nt 4-th and If I'am in 2nd or 3rd drive and giving more gas it is'nt shifting back. The failure has come in a second. Before it was good, after I had this. This is why I hope it is some electric failure and not mechanic... What can You say about it? Thanks

 

Could be a shift solonoid or even a stuck open thermostat can lock 4th out. To make the car warm up quicker thereby polluting less they locked 4th gear out until a certain engine temp. If the t-stat sticks open sometimes it cannot reach that temp.

 

Wow. how can I check it? Gives the OBD a code about the shift solenoid? Have You got the OBD codes to this modell? Thanks!

 

There is a self diagnostic connector under the hood near drivers fender,little black box. Pins are labeled. Jumping ground and ten is for engine control diagnostics using the check engine light flashs for codes but if your hold light is not flashing it will not have a code.

 

Do You know a list about the codes somewhere on the net? I hope I can read it at the weekend. To know what means the "ten long three short flashes" can be useful! I have something from the Hungarian Mazda forum, but I'am not sure about its similarity to the 929's codes...

 

1 long flash=ten, 1 short flash=1 . So watch the flashs closely. ten long and 3 short would be code 103 which does not exist. I can find the codes i'm sure if you can post them.

 

no code... I've conncted the TEN & GND and the CheckEngine was off. No flashes. I've tryed two times. Nothing.

 

Sorry. It is not ground and ten. It is ground and i forget so could you post what the little cap says on the diagnostic connector? Should be one that starts with a T. Like TAT or something. Then you count the hold light flashs.

 

I have this: http://www.mazdaklub.hu/forum/download.php?id=185

It looks right...

 

Hmm,well there was a TSB on the ECAT control unit on the 92 model. They did strange things. Wierd shift patterns etc but usually kicked numerous codes. If it has alot of miles and you have never replaced the thermostat then it would'nt be a bad idea nor a waste of money to do so. It is on the engine at the lower hose. Very easy to replace though a bit messy. Does the fluid look good? With no code i am hesitant to say a shift solonoid is bad as it should kick a code. I have seen turbine sensors do strange things but they normally effect all gears so i really have nowhere to go without having the car in front of me.