[FB07CC37]

My 07 Dakota 3.7 is showing a OBD2 code P0469. Evaporative Emission Controls (very small leak). Anybody seen this code? I know that sometimes a bad/ loose gas cap can cause it. Any other usual suspects? A hose? Purge flow sensor? Another sensor? I don't want to replace parts until the light goes out. But also would like to fix it myself. Thanks.

 

[oldmarine]

How did you get that code? According to my references, P0469 means "Purge Flow Sensor Circuit Intermittent". In the 2005 Dakota FSM, the codes for evaporative emission system LEAKS are P0442 (medium leak), P0455 (large leak), P0456 (small leak), and P0457 (gas cap loose). P0469 is not even referenced in the FSM.

Dakotas made after 2003 (and some late 2003) use Chrysler's Natural Vacuum Leak Detection system (NVLD). There are some codes specific to this system, so it's important to get the exact code.

 

[FB07CC37]

P0456

Thank you. My bad, I entered the wrong number - going by memory, sorry. I just went and ran it again. The correct code is P0456. I have an inexpensive Autel code reader and this is what is on the display:

P0456 $7E8 Generic
Evaporative Emission
System Leak Detected
(very small leak)

What do you think could be the cause?

 

[oldmarine]

Small leaks are usually due to cracked or loose fitting vacuum lines in the evaporative emission system. The purge valve is located in the engine compartment on the firewall near the power brake booster. It should have two vacuum lines going to it, one to the intake manifold or throttle body, and another going down and back to the canister. The charcoal canister and NVLD pump/solenoid are located on top of the fuel tank, and access is gained by removing the left rear tire and the splash panel in the fenderwell forward of the tire. There should be a vacuum line diagram under the hood somewhere that shows the location and routing of vacuum lines. If you know anyone who has a smoke machine, these can be very effective in finding leaks, especially small ones.

 

[FB07CC37]

Thanks for the info. I will start under the hood and check the vacuum lines before checking the pump and canister.

 

[jkelly16]

Leaky gas caps also will throw that code.