No, the magnets won't interfere with the signal. Magnetic drain plugs are so common I can't imagine that's a problem. And on mine, the magnetism goes away as soon as he probe is removed so cleaning will be even easier.

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Current Stable

• 380SL (diesel)
• Corvette C5
• Manx
• Baja Bug
• F350 Powerstroke
• Auburn Boattail Speedster replica