Nissan Repair: question about a 94 nissan altima, lockup torque converter, nissan altima

Question
i just bought a 94 nissan altima gxe. the overdrive indicator doesn't light up. the transmission seem to be stock in overdrive and during driving the RPM is higher than it suppose to be. at 50mph RPM is at 3000. i need help with this problem, what could it be.

Answer
Augstine,

If the overdrive does not apply and the light is not flashing there could be several issues.  First, check the fuse panel to make sure the power feed to the relay that locks the converter is not blown.  Second, there is a temperature switch that lets the 4th gear to apply along with the torque converter lockup.  Lastly, there is a vacuum switch that lets the comptuer know that the engine is not being loaded and that is the last link that allows 4th gear and the lockup torque converter applies.