The other day, my Check Engine light came on. I used my Diagnostic Tool to check it, and code P0442- EVAP System (Small Leak). I cleared the code, and it has not come back on since (I've probably driven the car 15 times so far). I have a couple small question related to this: 1) could it have been caused by a loose oil filler tube? I was cleaning under the hood and noticed it was loose so I opened the oil cap, jiggled the tube around, then JB-welded it back into firm place. I checked my gas cap and it was closed properly, but I re-sealed it just to be sure. 2) More importantly, every time I have used my diagnostic tool to check the car since, it shows a yellow light and says "Emission Related DTC's" but says no Powertrain DTC's or freeze frame data are present. A few of the monitors are flashing red (EVAP, O2, etc.) and I read that it could be because they havent yet completed their tests. When will it go back to green? All codes were cleared. Does it take a while?
My car has 90000 miles.
My car has an automatic transmission.
In order for all the monitors to clear you will have to do a lot of driving to see if it clears. The last two to clear take highway driving at a steady speed to clear and may take a couple times to clear or set a code if it cannot pass them after the testing has been done. The oil dipstick tube being loose will not cause the code you had. Keep driving the vehicle normal and it should pass all the monitors soon. I recommend having a qualified technician, such as one from YourMechanic, inspect the codes related to your Check Engine Light and diagnose the relevant systems more thoroughly in person.
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