overdrive 99 altima

activate the parking brake...engine off in Park, pull the transmission stick...it should be cherry red....not black...and come exactly to the mark enscribed on the stick...clean it with a rag...plunge it in and see...remember EXACTLY on the mark~ with the level at the correct position...the overdrive, which is a part of the transmission (not an extra deedles on the side) should operate correctly~ if this is indeed a separate doowhichy on the side, be sure the vacuum hose is not leaking or the electrical connection is solid and making the connection~

as far as poor performance, just how many miles are on this engine...have you changed your second or third timing belt by now...are you changing the air filter periodically~ how about the cabin filter? spark plugs, wires everything a happy car needs~ go get a smog check~ they will adjust things to make it run correctly!~

Just acquired. Everything looks to be in good shape. I have heard overdrive solenoid and speed sensor and possibly relay. How do I know which if not actual transmission