Check engine light can be on for many different reasons. If the check engine light came on after installing eFlexFuel, there is a reason to suspect that the device is not properly installed.


The first check the error code

  • If the problem is related to ignition, there is a reason to suspect that the wiring harness is connected incorrectly or badly.

Check for eFlexFuel fault codes with the eFlexFuel App.

  • Check the ethanol content to show the correct ethanol content.
  • Check the temperatures see that there are correct.

Check the eFlexFuel wiring harness

  • Make sure that the ground wire is properly connected. Car battery (-) is the best place for a ground wire.
  • Make sure that each connector on the cylinder and the terminals are properly connected.
  • Make sure that the male connectors on the cylinders are correctly with their polarities (multimeter part in the instruction manual).

Check the eFlexFuel connector pins are straight.

The eFlexFuel control unit has failed and needs to be replaced.