Fault codeP0018

MODERATE

Crankshaft Position Camshaft Position Correlation (Bank 2 Sensor A)

What this code means

Crankshaft Position Camshaft Position Correlation (Bank 2 Sensor A).

“Bank 1” is the side of the engine that holds cylinder number 1; “Bank 2” only exists on V and flat engines. An in-line engine has a single bank.

P0018 is a generic code: it means the same thing on every make. P0018 belongs to family P00xx — Fuel and air metering, auxiliary emission controls. Its page explains how to read a code and groups all its codes by part.

Camshaft–crankshaft timing

The control unit compares the signals from the crankshaft and camshaft sensors. On a healthy engine the two always keep the same relationship; when it drifts, the timing between the crankshaft and the camshafts has shifted. These codes do not point to a sensor but to that relationship.

What you notice

Often nothing at first. As the offset grows: rattle from the timing chain on cold starts, loss of power, harder starting, sometimes misfires.

How to check it

Do not ignore it: the most common cause is a stretched timing chain or a belt that has jumped a tooth, and a timing that slips further can let the valves hit the pistons. Check the oil level and condition first, since variable timing and chain tensioners depend on oil pressure. Then a mechanic checks the timing marks and the chain stretch.

Watch it live in Klaro

With an OBD2 adapter plugged in, these live readings show the part at work, when your car reports them:

Engine RPM
Timing advance

What to do

Have it checked this week. The car remains usable, but the fault will not clear itself and will fail the roadworthiness test.

Clearing a code switches the light off but repairs nothing: if the fault remains, the code comes back. Clearing a fault code yourself →

How to read this code

PPowertrain
0standardised code
0Fuel and air metering, auxiliary emission controls
18P0018