Time to take out the multimeter. Check the voltage at the plugs and at the relay, its a good place to start. I would suspect the GPR as well since it is unlikely that all the new plugs would go bad at once. If you want to pull one of the plugs and hook it up to the battery directly it should glow bright orange, verifying that the plugs are okay.

I have heard from others on this forum that a common symptom of the GPR can be correct voltage but not enough current to glow, so the voltmeter setting would be accurate but not enough juice to toast up the plugs.

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TC
Current stable:
- 2004 Mazda RALLYWANKEL
- 2007 Saturn sky redline
- 2004 Explorer...under surgery.

Past: 135i, GTI, 300E, 300SD, 300SD, Stealth