Servicing your vehicle, made easy.

Compare service professionals near you. Get multiple price estimates upfront. Schedule your service. Save upwards of 25% with Openbay+

How Openbay works

P0440 Diagnostic Trouble Code

Technical description

A general problem with the vehicle’s Evaporative Emission System.

What P0440 really means

The Evaporative Emission System in a vehicle manages the gasoline vapor that builds up in the tank through a system of collection into a charcoal canister, that will eventually discharge to the engine to be burned. Federal emission standards seeks to reduce the amount of gasoline vapor (hydrocarbons) leaked from a poorly sealed tank into the environment. The system is checked periodically by the computer for very minute leaks – usually .010” to .040” in size. This code is usually accompanied with a P0441, P0447, P0456 et. al., which further identifies and localizes the issue.

What are the symptoms of a P0440 code?

Do not fear, this does not mean that your car has fuel pouring or even dripping from the tank. This emission system is not looking for liquid leaks, and even though your gas tank may have small vapor leaks if it’s very old, the most likely culprits are rubber hoses or motorized vents which route the vapors to storage and then to the engine. For most of the driving population, these small vapor leaks go unnoticed – they do not effect performance or fuel economy.

What is the severity of a P0440 code?

Minor. Repairs should be planned to correct the problem, but there is no immediate danger of the car breaking down or performing poorly.

Get estimates for a P0440 diagnosis from nearby shops

What repair(s) are needed to resolve a P0440 code?

Rubber hose or motorized vent (exhaust system): Repairs should be planned to correct the problem, but there is no immediate danger of the car breaking down or performing poorly. Schedule a convenient appointment and expect to drop off the car for at least the day to be diagnosed and repaired. These small leaks or broken valves take time and patience to find.

What is the cost to resolve a P0440 code?

  • Estimated diagnostic cost: $100
  • Estimated part(s) + labor cost: under $100–?

Expect to pay a diagnostic fee of $100 minimum for a shop to diagnose the problem. However, the repair cost can really vary depending on what is found to be wrong and the type of car. A rubber hose in the system for most cars may be replaced for under $100 parts and labor. If any of the valves, the storage container, or the fuel tank (including the filler neck) are found to be leaking then the price can really climb. Many of the parts in this emission system are only available from the dealer.

Keep in mind, pricing will vary by location and your vehicle make and model. If you don’t already, save time and money by using Openbay to compare pricing and book an appointment with a service center in your area.

Service article written by an ASE Master Technician

Get estimates from nearby shops

How Openbay Works

  • Choose or describe your service

    Tell us what services you need, your maintenance interval, or describe your symptoms to request a diagnosis.

  • Compare estimates and choose a shop

    Compare estimates from local repair shops in the Openbay Network by distance, customer reviews, and price. All estimates include parts, labor rate and taxes.

  • Schedule an appointment

    Easily schedule an appointment right through your Openbay account. All services booked through Openbay are backed by our Peace-of-Mind Guarantee.

  • Manage your maintenance history

    When you create an account, your service history and upcoming appointments are always available online. Time to clean out the glove box!