Q: P0446 Check engine code

asked by on

I recently got my vehicle back from my auto shop with the check engine light on and prior bringing it there it was on. I have noticed it tells me to tigthen gas cap on my dash and the check engine light remains on. After reading the code it had multiple codes such as a P0446 code and a couple other P0 codes, one that relates to a circuit leak. Now I recently bought a new gas cap and tried replacing the gas cap but that did not work. I then recently tried replacing the EVAP vent canister and when I did I removed the old 2 port canister while the one I had purchased for my vehicle was a single port. I removed the other hose on my old canister because that one ran throught the undercarriage of my truck and was basically a air filter and the new one has a built in air filter. So I hooked the new one up and turNed my vehicle on, cleared the codes and left it running for 10 minutes. No check engine light for now, but it does still say tighten gas cap when I initially turn the vehicle on.HELP

My car has 89000 miles.
My car has an automatic transmission.

Hi there. The system will set the message if it attempts a self test and finds atmospheric pressure in the tank. The gas cap may not be the concern here as this message is directly related to a large leak in the system. This system extends from the filler neck, to the tank, to the engine, and the canister. Obviously, I would not think that a new canister is not failing, but it has happened before. A smoke test on the evaporative emission system will reveal any open leak in the system. There could also be solenoid malfunctions, loose wiring connections, or broken wires. Any of these can set codes, but the "tighten gas cap" message is simply a self check to make sure you have tightened the gas cap and not an actual diagnosis of the system. So many people have left gas caps loose and end up in the service drive over the check engine light; how would you feel if you were charged the door rate to have your gas cap tightened? I know the answer and I agree, I wouldn’t be happy about that either. I suggest having a qualified technician perform an inspection to avoid replacing unnecessary parts. Your Mechanic has several available technicians that can assist you with a check engine light inspection.

Was this answer helpful?

Need advice from certified mechanic? Get help now!

Over 1,000 mechanics are ready to answer your question.
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details
  1. Home
  2. Questions
  3. P0446 Check engine code

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Fair and transparent pricing

Get a quote

What others are asking

Q: Car has white smoke coming out of the left exhaust when idling or just after pulling off from a stop. Fine after that

Are you losing coolant? If so, the white smoke (steam really) is coolant being lost out of the exhaust. If the car only does this when first started in the AM, it may simply be condensation being burned off, which...

Q: my headlights along with the radio keeps shutting of and on repeatedly along with a few dashboard lights

You will need to have the charging system checked to see if the system is working properly. You may have electrical connection issues or component problems with the body control module and will need a mechanic like one from YourMechanic...

Q: Misfiring at high speed

Engine misfires can be caused by many different problems and are generally caused by either a spark or fuel issue or in some cases, a combination of both. Spark related problems generally will result from things like ignition coils, crankshaft...

Related articles

How Do Power Car Windows Increase Passenger Safety?
Power windows are responsible for approximately 2,000 emergency room visits every year. When a power window closes, it exerts enough force to bruise or break bones, crush fingers, or restrict an airway. Though...
What are the Car Pool Rules in Hawaii?
Hawaii is widely regarded as a land of vacation and relaxation, and as such, its scenic roads and routes are far better known than the state’s freeways. But, as with all...
P2103 OBD-II Trouble Code: Throttle Actuator Control Motor Circuit High
P2103 means there is a fault with the throttle actuator control motor circuit, likely due to a defective electrical component or part.