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Spark plug reading

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Old Yesterday | 03:11 PM
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Spark plug reading

New plugs with approximately 1500 miles. Motorcraft ARF42 gapped at .044
7 of 8 look exactly the same-perfect. 1 at the frontmost drivers side location is different;
Not sure if there's something going on here but I am chasing a random single ping that occurs only once the engine is fully warm.
Ping is not on acceleration or uphill but rather random.; literally its one or two pings,,, Just enough that I keep asking myself did just image that or was it real.
I can mash the gas pedal without a sound from the drivetrain.
I've re-checked gap on all plugs and installed a single new plug at that location and am getting some miles on it before I take a second look.

Any ideas whats going on here?
Thanks in advance
Tbruz

Passenger side L-R) backmost to front most
Passenger side (L-R) backmost to front most


Drivers side front to back-
Drivers side front to back-
 
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Old Yesterday | 07:17 PM
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Copilot says a Red Plug - indicates the following

Overheating and or abnormal combustion
Coolant or Oil intrusion
Incorrect or mismatched spark plug

Copilot explained more but you'd have to do a search.
What Causes the Red Color on Spark Plugs? — Ricks Free Auto Repair Advice Ricks Free Auto Repair Advice | Car Repair Tips and How-To Advice

Just a thought here: _ _ _ I'm throwing it out there for grabs. _ LoL
Ok, first off, when you pull a grade, your manifold vacuum drops with throttle plates open.
Now, at idle or in OD running little load, the manifold vacuum is higher. Therefore _ _ _ if that front cylinder has a slight intake runner leak, _ _ _ ping ping ?

ideas ?
 

Last edited by Greaser007; Yesterday at 07:32 PM.
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Old Today | 07:31 AM
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So I'd like to know about coolant intrusion in that cylinder. On an ice cold engine, I'd take my coolant pressure tester, pump it up, leave it for 30 min and watch pressure. If you've got a boroscope (lots available online for reasonable price) put it into cyl 5 (problem child) and see if there's any sign of coolant. As the water jacket is right next to that cyl, there could be a head gasket coolant leak (I truly hope not) but good to rule out.
 
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