Back in 2015 at a Ford training in Detroit, the instructor showed us a scan tool reading that made me stop trusting my ears for misfires.

Now I always hook up the scanner first, even if I'm 99% sure I can hear the skip, because that data stream showed a coil failing intermittently before it made any real sound.

3 comments

3 Comments

thomasw482mo ago

Scanners are great tools, but you can't replace a trained ear. I've caught plenty of rough idles just listening before a code even set. That data stream can lag behind what's actually happening in real time. Relying only on the scanner means you might miss the early signs your ears pick up. Why ignore one of your best diagnostic tools?

rileybarnes2mo ago

Exactly... scanners show you the numbers but your ears catch the rhythm. A misfire starting up might not trip a sensor right away, but you'll hear that hiccup in the exhaust note. It's like feeling a vibration through the steering wheel before the dash lights up. You gotta use all the clues, not just the digital ones.

the_spencer1mo ago

Used to think my ears were the best tool in the shop. That data stream proved me wrong.

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