1987 Olds 98 intermittent starting problem

I've got a 1987 Olds 98 Regency Grande coupe with the 3.8L engine and F3 suspension package. Over time, the coil packs have been replaced, this summer it got a new starter and battery. (that starter job was a bear with A/C and the stock "headers").

Anyway, in a completely random fashion (hot/cold doesn't matter) the car turns over just fine, but makes no attempt to catch. You can hear the fuel pump come on initially, and the rail has fuel pressure, but even after extended cranking, you never smell gas. I'm assuming that something is telling the fuel injectors not to come on, but what? It happens randomly and I've tried "tapping" relays and wiggling wires while the wife 'cranks' it, but after several attempts, nothing. Then I can walk away, come back 5 minutes later and it fires right up just fine. I'm thinking a flaky relay or sensor, but I don't know how to go about checking them. Or for that matter, are there commmon part failures that would cause this that it would be cheaper to just replace than to pay a fortune trying to get it scoped? It happens so randomly I'm afraid a shop will just keep trying to duplicate the failure and won't find anything unless it happens to fail.

On that year car with those symptoms I would just replace the troublesome crank sensor. It can be checked but only when it happens, maybe easier to just do it.

What did you do to get car to crank right My son 1995 oldsmoblie 98 is doing the same exact thing on starting accept it may not crank at all that day.When it do crank then after you cut it off you have to wait an hour to crank it again then it still may not crank.Some days are good when other are fustrating? Please help

You can try having your coil module checked I replaced mine after a crank sensor, battery, fuel pressure regulator, wires, ect. Now my 87 works beautiful!