Mercedes-Benz W202 diesel: EPC light on and the car goes into limp mode
Why is the Mercedes-Benz W202 diesel's EPC light on and the revs do not rise?
A common cause is the injection pump or its control electronics, for example the Lucas pump of the OM601 engine. First it is worth checking that no air gets into the fuel system, for example through the O-rings of the piping. Read the fault codes with a diagnostic tool before replacing parts.
What do the EPC fault codes P1224, P1231, P1482 and P1618 mean?
According to the discussions, P1224 and P1231 relate to the injection pump. P1482 relates to glow control and P1618 to the control unit. A code only gives a direction, so the fault should not be guessed from a single code.
Why does the Mercedes-Benz W202 CDI go into limp mode and lose power?
Common causes are a cracked boost hose, a vacuum leak and a dirty or faulty mass air flow sensor (MAF). A vacuum leak can open the turbocharger's wastegate, so the boost pressure does not rise. Check the boost hoses and vacuum hoses for cracks and read the fault memory.