Possible Causes for code P1309
PCM(power train control module), Mass Air Flow Sensor, Engine Coolant Temperature Sensor, Crank Shaft Position Sensor, Camshaft Position Sensor.
Now that we have an Idea of what the codes mean , we need to narrow them down. More than likely the problem is causing both codes to set. Keeping this in mind, lets concentrate on Code P1309. Of the possible causes listed above I see two Sensors that may throw up a lean code. I would look at the MAF Sensor
first and then the Temp Sensor
. You may find that if you remove the internal Sensor from the MAF Case that some degree has collected on the thin wire. If you find debree, use a Q-Tip to clean it. DO NOT USE CHEMICALS TO CLEAN IT. If no debree is found, try a Known Good MAF Sensor. Still no fix, move on to testing the rest of the Sensors on the list till you find the problem.
Keep in mind that the check engine light will have to be cleared after you have fixed the problem.