P0455 OBD-II Code

You might not think very much about your car’s gas cap, but that seemingly little inconsequential component of your car could end up causing you a bunch of worry.

With a gas cap that isn’t working exactly right, you’ll likely see your check engine light go on, and a OBD scanner code of P0455. 

The P0455 code is an indication of a large leak in the evaporative emissions system.

This can be caused by a faulty gas cap, loose or missing fuel cap, cracked or damaged EVAP hose, or even a bad purge valve.

If your vehicle has this code and you are trying to fix it yourself, there are some steps you can take to diagnose and repair the problem.

We’ll look at what causes this code and how to go about fixing it. We’ll also look at how much fixing the issue might cost you.

What is Code P0455?

Code P0455 is an indication that your vehicle has a large leak in the evaporative emissions system.

This code can be caused by a variety of things, such as:

  • A loose or missing fuel tank filler cap.
  • Cracked or damaged EVAP hose.
  • Faulty gas cap.
  • Bad purge valve.

Symptoms & Causes

Besides seeing the check engine light come on, you’ll likely not notice any problems with the way your car runs with a P0455.

However, one common noticeable symptom is a strong smell of fuel, especially close to the gas tank.

To fix the code, you should first check all of the components in the EVAP system for any signs of damage or wear.

This includes checking the gas cap, hoses, and purge valve.

If any of these parts are damaged or worn out, they should be replaced before you start looking elsewhere. Your mechanic should also check for any vacuum leaks in the system, which can cause the code to be triggered.

Usually, the problem starts and ends at the gas cap, which can be good news as it’s a relatively inexpensive issue to take care of.

You may just need to clean the cap or at worst, have it repaired, and that’s not really all that bad.

However, this is not always the case, and you may be looking at some more serious repairs.

Can I Drive with a P0455?

Yes, you can technically drive your car with this code, and as stated earlier, you may not even notice that anything is wrong.

However, it is important to note that if you are driving with a P0455 code, your vehicle may not pass a state emissions inspection.

Depending on the severity of the leak, you could also be damaging your vehicle’s fuel system.

Also, note that your fuel economy will not be optimal so you could be paying for more gas than necessary in the long run.

Cost to Fix

The cost of fixing a P0455 code can vary depending on the cause.

In most cases, replacing the fuel tank cap will only cost around $20-$30.

If you need to replace any of the other components in the EVAP system, costs can be anywhere from $50-$250 or more depending on the part and the complexity of the job.