Hi all,

Can't seem to shake this pesky ECM-439C code that I've had on a 2005 XC70 for a while now. Says Fuel Tank System Leak, Large leak. Check engine light on of course.

I have replaced the gas cap with a new Volvo gas cap. I verified that the latest software is up to date with DiCE as far as the control module (which makes it not as sensitive to leaks).

When I go to perform a "quick test tank system" in VIDA, I get an error message. The key is in position 2 as required, but the test will not initiate. Could this be a faulty leak detection pump?

This vehicle is emission code 2.

Thanks in advance for your help!

 

Hi, Did you ever figure out what the problem was? I have a 404c code (Fuel tank system, major leak). The only real symptom is lower fuel emission. I don't smell fuel outside the car. Maybe my problem is the same as yours was?