Mobile RFI (noise)

This is the place to post your general tips or ask questions about your installation, whether it's for mobile or base stations.
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Av8r1
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Mobile RFI (noise)

#117332

Post by Av8r1 »

It sounds as if I'm picking up spark plug wire noise. Do they make plug wires and spark plugs that would help that situation?


Thanks much. :roll:
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#117334

Post by 316 »

What do you drive Bill?
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intimidator_SS
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#117339

Post by intimidator_SS »

Yes they have have spark plugs that block rf most autoparts stores stock them and they usually have an R in the part number that means resistor. That basically means the cap of the plug where the plug boot "clips" on has more resistance.
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dud muck
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Re: Mobile RFI (noise)

#117348

Post by dud muck »

A vehicle more than 10 years old probably uses the high voltage plug wires.

Recent gasoline powered vehicles use coil-over-plug.

If your spark plugs have more than 25,000 miles on them. replace them.
As spark plugs age, their gap widens, which means more voltage required to make spark.
More voltage means more radio interference.

If you have the older vehicle with high voltage spark plug wires (not COP), then replace the spark plug wires.
Those high voltage cables are a "wear item" just like spark plugs.

Coil-over-plug does the voltage step-up right over the spark plug. The wires feeding the COP units are low voltage"vbat" at 13.8 volts, pulsed with about 6 amps of current. Often vehicles are missing a capacitor on the ignition wiring harness which would eliminate the radio interference problems :(

Even with COP, the spark plugs still wear the same.
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Av8r1
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#117528

Post by Av8r1 »

Thanks ! :lol:
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#117771

Post by Av8r1 »

New wire,plugs cap and rotor made RFI worse. Go figure. Now some one told me NGK lidium or some thing works good for that. Also is there a certain good quality wires and plugs that are best?


Thanks


ps Antenna off I get no RFI at all.

"95" Grand Cherokee
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