1994 Mighty Max 2.4L Will Start but not Run (At My Wit's End)

I have a 1994 Mighty Max that just died a few months back. While cruising along at 55MPH on the way home she just dropped out no pull. After towing home she will turn over and fire but not run, even trying to feather pedal. I checked/verified all timing marks, new plugs early last year with wires and distributor cap/rotor, spot on. Removed TPS, IAC, throttle body from another Mighty 2.4L and no change. Verified fuel pressure is in spec. And no change as well. ECU swapped with known good one and no change. (Should this have been grounded to function properly? I didn't actually bolt it in.) Also temp sensors are in spec. (Both ECU one and A/C one) CAT is clean as I dropped it to check. As you can see I am at my end now and very close to just wanting to blow her up! Only thing left to check is fuel rail (injectors, etc.) and/or possible vacuum issue. Please advise if you have had this experience before.

No one has a suggested solution?

Sorry I'm a first gen guy. But if it will run and idle it sounds like a fuel problem. Filter. or fuel psi regulator. And yes the ECU must be grounded.

I did do a filter swap a year ago. However I have not looked at fuel regulator... The!

I'd start with the basics. You say fire, so you are for sure getting spark? Did your check engine light come on? Have you checked for any stored codes? Could you have bad gas? When it cut out, did it falter like a fuel problem or just cut out like an electrical problem?

i had a similar issue with my 91 and it turned out to be a bad engine ground off the exhaust header to the firewall and a bad fuel pump.

If you havent already, try spraying some non-chlorinated brakecleen or ether into the throttle body and see if it fires. That will tell you which end isnt working, fuel or fire.
If it fires, then check the injector clips and see if they pulse while cranking, typically the ECU controls injector ground while they will get 12v full time with key. (So yes, most likely the ECU needs to be bolted in while trying a different unit)
If it doesnt fire, you can still check the above to make sure that end is working, and move on to either bad coil, or pickup in the distributor (ignoring possibly ecu and grounds)

It felt like a cut out of electrical. I already drained the tank/lines thinking bad gas. And the check engine light did come on but the next day was clear. No stored code.

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Originally Posted by harsity

It felt like a cut out of electrical. I already drained the tank/lines thinking bad gas. And the check engine light did come on but the next day was clear. No stored code.

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I'm not a second gen guy but that self clearing code may mean its losing electrical power because a ground is intermittently breaking the circuit.

I had a similar problem, if you still have the factory ground cable from the battery to the frame and then to the block try replacing the cable mine was corroded Inside the cable and had a very hard time running.