Code result
P03A4
Cylinder 2 Pressure Too Low
High severity
What it means
Cylinder 2 measured peak combustion pressure is below the calibrated minimum — typically low compression, weak injection, or stuck-open exhaust valve.
Is it safe to drive?
No — stop driving
This code points to a problem that can cause damage or affect safety. Avoid driving and have the vehicle diagnosed promptly.
Most likely causes
Low compression on cylinder 2
highOne of the most commonly reported causes for this code — check this first.
Related help
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