Code result
P28A8
Cylinder 7 Ion Current Sense Circuit
Moderate severity
What it means
The ECM cannot read a valid ion current signal from cylinder 7. Ion current sensing relies on the spark plug acting as an electrode after combustion.
Is it safe to drive?
Use caution
The vehicle is usually drivable for short distances, but the problem can worsen or affect emissions. Diagnose and repair as soon as practical.
Most likely causes
Ion sense module failed
highOne of the most commonly reported causes for this code — check this first.
Wiring or connector fault
mediumA plausible cause — test and verify before replacing parts.
Related help
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