CEL and seems derated

What engine do you have?

 

If you are using cruise to idle engine up that is normal. If you are using throttle pedal I would suspect a faulty throttle position sensor. Use the instructions below and you should get a code. If you do not have a diagnostic switch you will need to be hooked up to a computer.

Turn off the vehicle. To check for engine electronic fuel system and engine protection system fault codes, move the diagnostic switch to the "ON" position, or connect the shorting plug into the diagnostic connector.

Turn the vehicle keyswitch “ON”.

If no active fault codes are recorded, both lights will come on and stay on.

If active fault codes are recorded, both lights will come on momentarily, then begin to flash the code of the recorded faults.

The fault code will flash in the following sequence:

First, a WARNING (yellow) light will flash. Then there will be a short 1 (one) or 2 (two) second pause after which the number of the recorded fault code will flash in STOP (red). There will be a 1 (one) or 2 (two) second pause between each number. When the number has finished flashing in red, a yellow light will appear again. The three digit code will repeat in the same sequence.

The lights will continue to flash the same code until the system is told to do something else. To go to the next fault code, move the IDLE SPEED ADJUST switch momentarily to the "(+)" position. You can go back to the previous fault code by momentarily moving the IDLE SPEED ADJUST switch to the "(-)" position. If only one active fault is recorded, the CELECT™ Plus system will continuously display the same fault code when either "(+)" or "(-)" switch is depressed.

 

I believe on a M11 that is an injector circuit. Will have an injector harness issue or the injector itself is bad. Do you notice a miss in engine or smell raw fuel from stacks? I would say its number three injector but may want to check with somebody a little more versed.

 

Check oil level also you could be filling it up with fuel.

 

Possibly, it could have a bad harness or loose connection. You can smell fuel on dipstick if it's mixing. If solenoid is stuck it could be running great like it has lots of power.