Code result
P21EC
Cylinder 9 Injector B Circuit Low
Moderate severity
What it means
Cylinder 9 second-injector (B) drive line stuck low — short to ground. A flow-deviating injector throws off cylinder balance — adjacent cylinders run leaner/richer to compensate, often masking the root cause until the trim limit is hit.
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
Short to ground
highOne of the most commonly reported causes for this code — check this first.
Connector pins corroded - high contact resistance
lowLess common, but worth ruling out after the more likely causes.
Harness chafing through insulation
lowLess common, but worth ruling out after the more likely causes.
Related help
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