P0172 99’ Tacoma

Was supposed to be leaving for a big trip today but check engine came on and hit for P0172- fuel system too rich. Trying to diagnose/fix now before I leave.

Car does seem to be running fine right now (no serious idle issues, etc.)

Below are steps I am taking, any input would be much appreciated

Step 1: Thermostat

-probably not most common starting point, but I had issues with leaky gasket recently, figured I would try to see if thermostat was stuck open.

-started car and idled with heat blasting for 6-7 minutes, air got warm but not super hot. Somewhat inconclusive so on to next test

-drove car for a bit 10 minutes or so to really get up to temp. Temp gauge read normal, park car and radiator hose was pretty hot. This has me thinking thermostat is working properly.

Step 2: Mass Airflow Sensor

-seems to be a common issue when this code throws. Going my to remove the air intake and inspect the sensor, clean if needed. Will report back.

Step 3: Spark Plugs

-check for abnormalities.

Any tips or advice would be great. Hoping to not have to go through every solution/spend a time of money.

 

Update: sensor didn’t look bad but cleaned it anyways. Honestly think the issue was that my air filter box was not closed properly and was loosing vacuum seal. Unplugged battery and reset codes and nothing has come back on yet.

Also replaced PCV valve as it was filthy but still rattled but ehhh it a cheap part.