fuel filter....

A fuel issue usually causes the engine to gag, or shutter, etc. before it completely dies. If you're going along perfectly fine, and then it just instantly dies without even blinking, it'* more than likely an electrical problem. You can try an ECM, but I'd save that as a last resort. Many parts places test the coils and ICM for free. It wouldn't hurt anything to take those in and find out if they're bad first.

Does it die as soon as you start it, or after you start it and put it in gear? If the latter is the case it needs a torque converter lock up switch.

I had a similar situation with my daughter'* '91 GP. The first time, replacing the crank sensor took care of the problem. It'* low on the backside of the engine and is a stretch to reach. The plastic cracks and warps which makes it intermittent. That took care of the problem until 3 months later when the ICM went...same symptoms.

The crank sensor was only about $30, and is held in with one bolt. Reaching it is the hardest part. The only accurate way to test the ICM is by replacement. You should be able to pick up a used one at a junkyard. If you're getting no spark when it dies, it'* likely one of these parts.