P0442 - Smoke Testing

Post by **br0dy519** » 31 May 2020, 15:48

Hi all,

Wife's 2004 XC70 has the dreaded EVAP Leak. I've done the following:

1) Swapped fuel cap with my S60 , engine light returned and my S60 is flying with no xmas lights.
2) Leak detection pump test on VIDA, comes back OK
3) All software updated to latest Rev from dealer
4) Tested and replaced the failed purge valve (verified w/ battery test, solenoid not moving)
5) Visually inspected J-hose, couldn't find any split/rot/leak source there (Had to use phone/mirror to see, it's in a crazy spot above the prop shaft in this car)

It is time for me to do a smoke test. I know how I'm going to make the smoker. I'm wondering where I'm supposed to plug the smoker in. Is the recommended place on that snap/compression fitting that I removed from the purge valve? Looks like a 1/2OD hose that I would use.

Thanks guys. Couldn't find this info in my exhaustive searches.

Post by **jimmy57** » 31 May 2020, 16:07

You can use the hose to the purge valve for the connection and you have to seal the vent hose that runs up the filler neck and will have a cylindrical filter at the end. I have some rubber cap that I keep anytime a part has fittings capped off. A short length of the right size hose with something stuck in it will act as a cap also. The canister vent is normally open and is only closed to do leak test by the ECM so it will be open and smoke will come out there without finding the real source. J hose is often leaking but not found by visual inspection but when smoked it will show smoke

Post by **br0dy519** » 31 May 2020, 16:58

Thanks Jimmy. I'll make sure to cap off the other end of that vent canister.

Any tips/tricks to replacing the J-hose on an AWD car? Only seen mention of FWD being accessed above the heat shield above the muffler which seems irrelevant in my vehicle.