Fault code

P0306 fault code.

This code comes up with one known fault.

Generic code

Code type

Engine and drivetrain

System

Misfire on cylinder 6

The engine control unit detects a misfire from the momentary slowdown of the crankshaft, and tied this one to cylinder 6. An ignition coil, a spark plug, an injector or a leak can all cause it. The repair is often a new spark plug or a new ignition coil.

The code tells you what the control unit measured, not which part has failed. The same code has several possible causes.

Which known faults it comes up with

B5: early failure of the ignition coils

comfort

The per cylinder ignition coils fail early: jerking, misfire, a flashing engine warning light, limp mode. Typically several age at once, and after a replacement the new ones can go early too. The phenomenon occurs on every B5 engine, not only the turbocharged ones.

What to check

After a cold start watch whether the idle is even and whether there is shaking
Under load (overtaking, a slope) check whether it jerks
With a code reader look for per cylinder misfire (P0300 to P0306)

1 more steps in the write-up

Information, not an expert opinion

We write the descriptions, and we put the source next to them. A person reviews them before they go out. They are still information, not a technical expert opinion.

A fault on the list does not mean the car you are looking at has it.
A fault missing from the list does not mean the model is fault-free. Write-ups are made model by model. Not all of them are done.
You decide whether to buy. This is no substitute for an inspection. That needs a workshop and a history check.

Details in the terms