!999 Corolla Starting problem?

I have already posted about this problem but have concluded a few things. My car will spuratically not start and have concluded its not the battery and thats all! This is definite though the past 4 times it wouldnt start I was able to get it started by tapping on the alternator while the ignition key is being turned. This is not a coincedence it starts right away when this is done and no one can figure out why? I told two mechanics what is happening and they dont see how this could be happening. Can anyone tell me how this could be happening? Honestly all you have to do is tap it lightly this is driving me crazy

My money is on a bad ground wire. Have you tried tapping anywhere besides the alternator? If you do and it starts, that will pretty much confirm a bad ground. Or try this. Keep a jumper wire with aligator clips in your car. When it doesn't start, try connecting one end of the wire to the firewall, fender, or radiator support and battery negative. If that works, you have a bad ground to body. Or use a jumper cable from the engine block to the negative battery terminal. If that starts it, you've got a bad battery to engine connection.

Next time it happens I will try tapping it somewhere else. I did check all the ground connections and they seem fine used a continuity tester. The starter is not far below the alternator maybe its vibrating through to the starter? Will see next time it happens.

I have already posted about this problem but have concluded a few things. My car will spuratically not start and have concluded its not the battery and thats all! This is definite though the past 4 times it wouldnt start I was able to get it started by tapping on the alternator while the ignition key is being turned. This is not a coincedence it starts right away when this is done and no one can figure out why? I told two mechanics what is happening and they dont see how this could be happening. Can anyone tell me how this could be happening? Honestly all you have to do is tap it lightly this is driving me crazy
check and clean the earth wires to the motor from chasis or battery
also could be low on brushes in starter

Well it wasnt the battery terminals,grounding or the alternator. I took a chance and changed the starter because that seemed to be what most everyone was telling me to do and that was the problem. Actually it was probably the starter solenoid either way its fixed!:)

It may have been the contacts in the solenoid which would have set you back $30 and labor.

See here: http://www.automotiveforums.com/vbulletin/showthread.php?t=645352