1991 intermittent sputter
 

A co-worker has a Civic with a problem. It is a 91 DX and it started sputtering when driving awhile back. It is a fairly violent sputter and seems to be a complete cut of power not just a drop. But it only happened for a fraction of a second and then would drive normally for anywhere from a couple minutes to a few hours after. It happens under normal throttle, usually at a steady speed. No warning lights would come on and there wasn't any blip in any of the electronics in the car.

Then it died completely when going through an intersection. It would crank but not fire so it was towed to the dealership. They replaced the igntitor, the coil, fuel filter, cap and rotor and said "fixed". It drove fine for a few days then it sputtered again.
So they replaced the plugs and wires and valve cover gasket (oil was leaking into the spark plug tubes) and said "fixed". It drove fine for a few days but is now sputtering again. It can go for an entire drive without doing it though.

Any suggestions to avoid having them continue to charge a fortune to just throw parts at it?

I'm thinking with all the ignition components replaced it pretty much has to be a fuel issue but he is still paying for the other repairs so hesitant to just start throwing parts myself at it.

He's really not very mechanically inclined, thus paying them for all those repairs. But I can help him with some of it.

I initially thought that it was a clogged fuel filter. Why won't he have it checked my a competent mechanic just to be sure?

There's the really fun part. We actually work at a Honda dealer so he has them working on it here since he gets employee pricing.

They are supposedly diagnosing the problem but so far they've replaced:
cap
rotor
ignitor
coil
fuel filter
plugs
wires

With pretty much everything associated with spark being new it leads me to think it is a fuel issue; maybe an injector problem.