99 V70 evap code P0455

Shappy · Post by **Shappy** » 08 Dec 2015, 19:52

Bought a Haynes manual hoping to understand and diagnose the evap system. What a waste of time and money! Absolute junk! Anyway can anyone advise the most likely culprit for this code? Is it the solenoid on the fan shroud, the gas cap, or is there something else more likely? Other than the charcoal canister is there anything else in the system? Where is the canister located? I looked up under the fender ahead of the left front wheel and saw nothing. Wagon has 145k kms total from new, runs great. Thanks for suggestions! Bob

Post by **cn90** » 08 Dec 2015, 20:08

Yes, you are right.

Below is the EVAP thread:
https://www.matthewsvolvosite.com/forums ... hp?t=54546

Please note:
1. I installed a Bosch (made in China) purge valve, it fails in 2.5 years!

2. Just replaced with a Pierburg valve.

All info in that thread, read it carefully.

PS: In a gasoline system there is always a slight pressure (maybe 1-2 psi above atm pressure) simply b/c of gasoline evaporation.
However, in order to test the integrity of the EVAP system, the car mfg's take advantage of the free Intake Manifold vacuum to perform the self-test at start-up and during drive cycle. In other words, you can also test the system using some pressure, but the car does not have an air compressor, it only has vacuum (and it is free vacuum).

Post by **abscate** » 09 Dec 2015, 03:47

In your 1999 the canister moves to the back in front of the rear passenger wheel, RHS

Anyone who saw LA smog in the 1970s doesn't sweat emission control stuff and EVAP is the most important.

Post by **bmdubya1198** » 09 Dec 2015, 09:03

Most of the time it's the purge valve.