Hi all
Replaced the original Motorcraft plugs in the car in my sig with NGK Irdium IX. Had them gapped wrong, took them out and regapped to original spec. for the engine.
Now on start up, I can feel the engine shuddering from misfires, this was never present before. They aren't misfiring enough to throw a code but it is perceptible. Not sure what to do, ignore it since no codes, or replace them with the OEM plugs, or gap them back to the .54 they are spec'd at by NGK (vs. the .35 spec'd by Ford on their OEM plugs).
This engine used to purr like a kitten. Not even the slightest shudder.
The intake does have to be taken off for this 3.5, not sure if I didn't get the torque on the intake gaskets right but if anything they're over-torqued, the torque wrench I had stunk. I didn't replace them because they had only been on for like 6 months before I had to take it off to re-gap.
Replaced the original Motorcraft plugs in the car in my sig with NGK Irdium IX. Had them gapped wrong, took them out and regapped to original spec. for the engine.
Now on start up, I can feel the engine shuddering from misfires, this was never present before. They aren't misfiring enough to throw a code but it is perceptible. Not sure what to do, ignore it since no codes, or replace them with the OEM plugs, or gap them back to the .54 they are spec'd at by NGK (vs. the .35 spec'd by Ford on their OEM plugs).
This engine used to purr like a kitten. Not even the slightest shudder.
The intake does have to be taken off for this 3.5, not sure if I didn't get the torque on the intake gaskets right but if anything they're over-torqued, the torque wrench I had stunk. I didn't replace them because they had only been on for like 6 months before I had to take it off to re-gap.
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