On 1987 & later 2.3's the timing is crankshaft(flywheel) controlled & non-adjustable! The distributor only allows the spark thru to the correct plug!
BY moving the distributor from its base setting you can cause cross-fire.

AT TDC there is a punch mark on the distriburor housing that MUST align with the center line of the rotor.

TRY different fuel stations & a different brand of fuel. IF that doesn't help you might have excessive carbon build-up.

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