Nissan Repair: 93 300zx stalls when in neutral on bumps, bump in the road, brain box

Question
Hello, I test drove a 93 300zx, manual trans, non-turbo, with 187,000 miles.  The car started, idled, and ran fine.  During the test drive, I pushed in the clutch and hit a small bump in the road and the car died.  It started right up again without any hesitation.  The owner said that it has happened to him in the past going over bumps or RR tracks at slow speeds in neutral or with the clutch depressed.  He said that the car has never had a tune up.  Do you think a tune up & new fuel filter would solve this?  What other maintenance should I be wary of?  Thank you.

Answer
Clint,

Find the computer module and while the engine is running at normal operating temperature slap the box.  If it dies the computer connections are loose and need to be reseated.  Other thoughts on the electrical connections being loose at the steering column.  But, from the dies in neutral over bumps it sounds like the brain box connections to me.