When the code is set
The ECM uses the crankshaft position sensor to monitor how smoothly the engine turns. Each misfire in cylinder 2 briefly slows the crankshaft at the point that belongs to that cylinder. When too many misfires build up within a set time, it stores P0302; with severe misfires the check engine light flashes.
Can I keep driving?
Have it checked soon
If the check engine light flashes, stop when it is safe and do not drive on: unburnt fuel can destroy the catalytic converter. If the light stays on steadily and the engine runs almost normally, drive gently without hard acceleration and have the car checked as soon as possible. If the engine shakes badly or loses power, it is better to have it taken to a garage.
Symptoms
- The check engine light is on or flashing.
- The engine shakes, especially at idle.
- Jerking and less power when accelerating.
- Hard starting.
- Higher fuel consumption.
Common causes
- A worn or fouled spark plug in cylinder 2.
- A faulty ignition coil or spark plug lead on cylinder 2.
- A clogged or faulty injector on cylinder 2.
- An air leak at the cylinder 2 intake port.
- Low compression in cylinder 2 from worn valves or piston rings.
How to find the cause
A mechanic usually works like this:
- Read all stored codes and freeze frame data.
- Inspect the cylinder 2 spark plug; if the plugs are old, replace them all.
- Swap the cylinder 2 coil and plug with those from a neighbouring cylinder and clear the code. If the fault moves, the swapped part is to blame.
- If the fault stays in cylinder 2, check the injector.
- Finally, run a compression or leak-down test on the cylinder.
Other ways the code is written
Scan tools and workshop printouts sometimes show the code with extra characters:
- P030200
Related codes
Frequently asked questions
Evoca fault code diagnostics is an informational aid and does not replace a professional inspection of your vehicle. Only an inspection of the vehicle at a workshop can confirm the cause of a fault.
Check P0302 for your car
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