GM OBD Trouble Code 52

Fuel cal-pak incorrect or missing

If the ECM detects an internal fault with the Fuel cal-pak or the Fuel cal-pak is missing, code 52 will set. The Fuel cal-pak is a special "chip" that is installed in the ECM, based on the particular vehicle configuration.

Fault Code Description

  • 52 - Fuel cal-pak incorrect or missing


  • Engine may not start
  • Poor engine performance

Common Problems

  • Internal fault with Fuel cal-pak
  • Fuel cal-pak incorrectly installed in ECM

No comments yet...

Sign in to comment

Related Questions

See what others have asked about this, or visit the Questions page to ask your own question.
My truck has 310k miles on it and just got a new alternator. normally in an older vehicle, i'd think i should replac...
Do i ha ve to flash or reprogam new ecm