I did check the search but didn't find anything with my same details.
I just picked up a 96 2wd XE 5sp with 230,xxx miles on it. Its in pretty good condition but it wont start. I bought it knowing this.
I went to look at it knowing it wont start but while we were there I tried to jump it and it fired up and ran great. It continued to start for about a day (4 or times) then just clicks again.

Here are the things I've checked and the details...
The PO said he replaced the starter less than a year ago because it wouldn't start. It worked fine for a few months and then started occasionally not starting again.
So I looked it up and figured it was just bad batt terminals or a relay. I got it home, got the battery charged up (its a bad battery, but it still started it) fiddled with the relays and terminals and make sure everything looked good. It still decided not to start or crank, even when being jumped from a running vehicle.
When I turn the key I hear the click from under the dash, I hear and can feel the interlock relay clicking (even tried jumping the #3 and #5 term to double check). I feel the clutch switch is good because if I turn the key and then depress the clutch I can hear the power move forward and (heres the twist) I can hear the starter clicking pretty strongly, but the bendex gear is not engaging and the starter is not turning. I took the starter out and had it bench tested again and it is strong.
The vehicle push starts just fine ( I coast it down my steep driveway in second and let the clutch out, works flawlessly).
At this point I am at a loss and don't know what to do besides always park on a hill.
Any help would be AWESOME, thanks in advance.

Just cause a starter works fine during bench testing doesn't always mean it will work under a load. If your battery and cable along with their connections are good, if you are getting power to the starter solenoid when the key is turned to "start," then I would replace the starter, preferably with a genuine Nissan reman. part. Aftermarket starters and alternators tend to be a bit of a gamble, especially on the Asian makes.

That is where I am at the moment also. I am going to put in the battery from my other car that I know is good just to make sure and then if that doesn't help I will make napa replace this starter weather it tests good or not and use that until I can afford to get one from Nissan.
It may be pushing the gear out but not with enough force to engage with the flywheel gears and turn it over. Thanks for the back up on that thought. I will follow up here with results as I go to help anyone else that comes across a similar issue.

So I have solved my starting issue... Here are the details..
I pulled the starter and had it tested again and again it tested fine... On the bench. I told them I have completely gone through the truck and it has to be the starter and I insisted that they replace it. So I got home and put the new starter in and went to start it and again only got a click from the starter area. So I fiddled with the battery terminals and the dang thing fired up. They all felt pretty tight but obviously there was some corrosion or a bad connection somewhere.
I cut back a couple inches of the battery cables and bolted on some new ends and it has been working perfectly for about two weeks now...
Someone here had mentioned that the Nissan's are very picky about the battery voltage and clean connections and I have been doing all my own work for about 20 years but they were right, even though it all looked clean and tight there had to be just enough of a lose battery terminal to not allow it enough power to crank the starter under a load.
Thanks for the help, I am loving not having to push start it at work every day now...