P0302 fault code: Cylinder 2 Misfire Detected
Last updated · OBDCode UK editorial
Our verified driving guidance for P0302 is: limited driving. If the engine management light flashes and the car judders, stop: the linked coil-swap check overrides this to do not drive. Do not keep driving to 'clear it'.
Can I DIY?
Caution — conditions apply. We do not publish DIY repair or strip-down steps for this code on this page. Read codes and observe only; leave the repair to a qualified garage.
Some checks may be possible for a careful DIY driver with the right tools and a safe place to work. Stop if anything feels beyond your skill or kit.
Never idle in a closed garage to read codes — an open door is not enough. CO is odourless and can kill. Run diagnostics in open air. Headache or nausea with exhaust smell: get fresh air and stop.
What does P0302 mean?
P0302 is a generic (SAE standard) powertrain code reported by your car’s engine control unit. It sits in the P03xx block, which covers ignition system and misfire. The stored description is “Cylinder 2 Misfire Detected”. The code itself tells you which circuit or system tripped the fault — not always the exact part that failed.
How to diagnose P0302 yourself
- Confirm cylinder 2 and the lamp state: Scan while parked in open air. Record P0302 as current or pending, freeze-frame rpm, and any other cylinder misfire codes. Write down whether the engine management light is steady or flashing. Do not clear the code to 'see which coil it is'. Stop if: The lamp is flashing, the car judders badly, or you smell exhaust in the cabin.
Park safely and switch off before locating the socket. Its position varies, so use the vehicle handbook and never force or dismantle trim. - Judge idle and lamp from outside the car: In open air, start the engine and stand outside. Note whether idle is even, whether the lamp flashes, and whether the car shakes. Switch off after a short look. Do not unplug coils, remove plugs, or go under the car. Stop if: The lamp flashes, the engine shakes hard, coolant temperature climbs, or anyone in the car feels sick from fumes.
A flashing engine management light means stop safely and arrange recovery, whether or not you feel judder. A steady light still needs prompt diagnosis, and becomes a stop if it starts to flash, judder or lose power. - Read cylinder 2 misfire counts if shown: If the scanner shows per-cylinder misfire counts or fuel trims, note cylinder 2 versus the others at idle outdoors. We do not publish a pass/fail count. Do not swap the cylinder 2 coil with another cylinder from these instructions. Stop if: Counts climb quickly, the lamp starts flashing, or you would need to disconnect ignition connectors to learn more.
Will P0302 fail an MOT?
An illuminated engine management light is a Major defect at MOT until the lamp stays off. A misfire that produces excessive smoke can also fail the emissions test. Do not take a flashing-lamp car to a test.
Before booking your test, check what usually fails on your car: see our MOT pass rates by make and model, built from 33.1 million DVSA tests.
What the MOT data says
These figures are copied from the MOT fail cohort for the certificate wording below. They are not a diagnosis of this car.
Certificate wording: “Malfunction indicator lamp Engine MIL illuminated indicating a malfunction”.
Of 391,384 Class 4 vehicles that failed a 2024 MOT on that wording, 14.8% (95% CI 14.7–14.9) failed on the same wording again in 2025. The not-tested gap versus control was 11.5 points.
Certificate wording: “Catalyst emissions Lambda coefficient outside the default limits or the range specified by the manufacturer”.
Of 166,607 Class 4 vehicles that failed a 2024 MOT on that wording, 7.5% (95% CI 7.4–7.6) failed on the same wording again in 2025. The not-tested gap versus control was 13.4 points.
Engine management light MOT outcomes
Related guides
Related fault codes
P0302 — quick answers
Is it safe to drive with P0302?
Limit your driving. Our verified driving guidance for P0302 is: limited driving. If the engine management light flashes and the car judders, stop: the linked coil-swap check overrides this to do not drive. Do not keep driving to 'clear it'.
Can I fix P0302 myself?
Caution — conditions apply. We do not publish DIY repair or strip-down steps for this code on this page. Read codes and observe only; leave the repair to a qualified garage. Basic tools only — for example a household socket set, tyre gauge, or a consumer OBD reader.
Will P0302 fail my MOT?
An illuminated engine management light is a Major defect at MOT until the lamp stays off. A misfire that produces excessive smoke can also fail the emissions test. Do not take a flashing-lamp car to a test.
Fault-code identifiers are standard diagnostic facts. Their explanations and diagnostic guidance on this site are original editorial summaries, not reproduced SAE wording. MOT defect rules reflect the DVSA MOT inspection manual (2026). This page is general guidance for UK drivers, not a substitute for a professional diagnosis.