Zak

My friend has a 1990 240SX. She bought it for a very low price because it had a bad automatic transmission, which I replaced last week with one from a junkyard[0]. I am now experiencing the following problems:

• The transmission does not shift automatically; D seems to start in second and stay there. Manually selecting 1st is the only way to start in 1st.
• Kickdown does not work, though I can hear the switch being activated when I press the trottle down.
• It won't shift in to 3rd when in D.
• The torque converter does not lock up.
• The transmission shudders at speed, especially around 35mph and over 60mph.

I have checked the following:

• Fluid: it is properly filled with Dextron III fluid.
• Electronic plugs: all the plugs that exist are plugged in. There is one three-pin plug on the car side that has nothing to plug in to. My multimeter shows no change in resistance between any of the pins in response to the kickdown switch.

I'm fairly ignorant about automatic transmissions; I've never owned a car with one. I REALLY do not want to change the transmission again, as I don't have a proper place to do the work. Does anyone have suggestions on what to try next? I am planning to change the fluid and filter next week. Is there a cleaner additive I should run in it for a few days first? Is there an additive or specific kind of fluid I should put in when I change it?

[0] Yes, replacing it with a manual would have been better. It also would have been twice as expensive. The idea here is low-budget transportation that doesn't suck, not performance.

wikd240

i just posted how to put the transmission into diagnostics mode without the consult tool from nissan in another thread... here is the link to the post...

http://www.club240.com/forums/showth...threadid=25916

good lick as i am having some of the same problems with my a/t... my codes say it is the speed sensor and the rev sensor that are either disconnected or shorted out... i replaced the speed sensor lasnight and i am going to try to find a rev sensor but s far no luck... must be a dealer part...