P0291

DTC P0291, sometimes indicated as P029100 is an OBD diagnostic trouble code indicating a generic fault with the vehicle powertrain (i.e. engine and gearbox). This code identifies an error with the air/fuel mixture causing cylinder 11 injector circuit low.

The code P0291 is set when the PCM (Powertrain Control Module) detects a low voltage in the injector circuit for cylinder 11. This can be caused by a number of things, including a bad injector, a wiring problem, a bad PCM, or a problem with the fuel system.
If you have a code reader, check the live data for cylinder 11. If the voltage is low, then you know that the injector is not functioning properly. If the voltage is normal, then the problem is likely a wiring issue or a problem with the PCM.
If you have a wiring problem, the best way to troubleshoot it is to use a voltmeter to check the voltage at the injector connector. If the voltage is low, then there is a problem with the wiring. If the voltage is normal, then there is a problem with the injector or the fuel system.
If you have a problem with the PCM, the best way to troubleshoot it is to swap it with another PCM and see if the code goes away. If the code goes away, then the original PCM is bad and needs

• P0291: Cylinder 11 Injector Circuit Low
• P0291: Cylinder 11 Injector Control Circuit Low
• P0291: Injector 11 – circuit low
• P0291 00: Cylinder 10 injector - open or short to ground
• P0291 00: Injector 11 - circuit low