Q: I got a code for my EVAP (P1457)

asked by on

This code is meant for my EVAP. I recently replaced my purge valve, charcoal canister, and the solenoid and all my hoses are crackless, and also my plug that attaches to it is clean and intact. I can't seem to find the problem, there's supposably a small leak somewhere. One of myfriends, says it's my PCV valve. Is this possible? What do you think is the best possible thing to do. If it isn't that one part.

My car has 151000 miles.
My car has an automatic transmission.

First, it is not the PCV. (positive crankcase ventilation) The PCV is there to relieve pressure and gases from the crankcase. The evaporative system keeps the fuel in the fuel tank from evaporating into the atmosphere. They are two separate systems.

This particular code simply states there is a problem with the evaporative emissions system. It doesn’t really point to any one thing wrong, such as a leak. Since this code is so generic, a total system test will need to be run. This can only be done with a shop level scanner and a technician with the experience to understand the results. Evaporative system tests will activate all the valves and solenoids in the system in a fashion that will reveal what to look for. It could be a leak, a solenoid that is not working or a sensor that is reading incorrectly. There are pressure sensors on the fuel tank that are used by the system to check for leaks. This is done by using the vacuum in the engine to put the fuel tank into low pressure. If the tank does not hold this low pressure condition, a code will be set. This is a simplified version of the test. If the sensor is showing an incorrect value, the system will assume there is something wrong.

If it is a leak that needs to be chased, the most common place for leaks in an evaporative system, are the seals that seal the hose connections. When these seal dry, they contract and begin to leak. The best way to look for any leak in an evap system is through the use of a smoke machine. Unfortunately, smoke machines are expensive. It creates pressure in the evap system and injects smoke into it as well. Smoke will escape out any leak in the system.

Because of the tools involved and the complicated nature of evaporative emissions systems, I recommend the following inspection to help you out. Check engine light is on inspection

Good luck!

Was this answer helpful?
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. I got a code for my EVAP (P1457)

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: How much is a shift linkage replacement

Hi there. It really depends on whether the pin itself is damaged or if the shift linkage or shift cable is damaged. If it's a minor repair, budget $200 to $350 for most local shops. If it's replacing the shift...

Q: My car won't start. Lights on the dash work headlights windshield wipers I had got a jump but my car still won't start. My key rem

It sounds like you may have a battery that is too weak to be jump started or to power the door locks. I would suggest taking the battery to your local auto parts store to have it load tested. This...

Q: My car won’t start. The lights and radio comes on but it won’t turn over

Depending on whether or not the vehicle will turn over will determine what the next step should be. If the engine does not turn over, I would recommend checking all connections related to the battery and check to be sure...

Related articles

P0240 OBD-II Trouble Code: Turbocharger Boost Sensor B Circuit Range/Performance
P0240 code definition Turbocharger Boost Sensor B Circuit Range/Performance What the P0240 code means P0240 is an OBD-II generic code triggered when the Engine Control Module (ECM) detects the intake boost...
Rules of the Road For Iowa Drivers
Driving on the roads requires knowledge of the rules, many of which are based on common sense and courtesy. However, even though you know the rules in...
How to Avoid Back Pain in a Car
If you have back problems, sitting in a car for an extended period of time can be excruciating. Even without back problems, you could experience discomfort and soreness from...