DIY "fixing" ECM plugs and other things often creates
More problems now or down the road in middle of night or on highway in rain far from home.
Those Plugs are likely just fine
but ECM is dying causing problems.Most ECM "Dies" from heat and crack solder joints. Plus Many Old GM ECM units have problems right from the factory because board "paint" swells and can crack chips off the board.
Just Touch the plugs will often make the board to move some and set off crack joints. More so when you remove ECM cover that is part of mounting the board in it and heat sink for driver "chips" "bolted" to the intermediate heat sink on the board.
A GM official test is to tap the ECM w/ fingers and watch motor and MIL. This Tapping along can set off crap joints anywhere on the board and motor instantly dies or has other problems, set bogus codes, etc.
1 typical example w/ this ECM is no "signal" to run fuel injector after running then parked over night. The driver chip (1 of several MOSFETs) has crank joint(s) for heat cycling and cooling down finally "kills" it and won't start.
But This Won't kill the Fuel Pump unless FP wiring has other problems because Oil Pressure Switch will keep that On even w/ FP Relay turns off or dies.
Save the PROM to use w/ new/rebuilt ECM from Cardone etc.
See my Cave,
ECM Heat------------------
Dr. Ian Malcolm: Yeah, but your scientists were so preoccupied with whether or not they could, they didn't stop to think if they should.
(Jurassic Park)
The Ogre's Fiero Cave