Check Engine Light (CEL),yet no codes

I have an 06 Mustang GT with a few minor mods. One of them being an intake and a tune. Every once in a while I will get a CEL. When I plug in my handheld tuner to read the trouble codes, no codes are found.

Does the tuner have the capabilty to check for pending codes? If not, take the vehicle to a local Auto Zone and ask if they can connect a code reader to see if there are any pending codes. They’ll do this for free.


It can check for P codes.

Is your scanner CAN compatible? Not all OBD2 scanners will work on all OBD2 cars.

The “P” in P codes does not stand for pending, it stands for Power-train.

CAN compatible? The hand held tuner does scan for P or powertrain codes. I have had P0171 code (too lean) bank one and P0430 and P0431 come up before. I replaced my 02 sensors and cleaned my MAF sensor and those codes have not shown up. Also the hand held tuner/scanner is compatible and is locked to my car. I use the tuner to load email performance tunes into the car.