Purg Valve update

0230683 · Post by **0230683** » 12 Dec 2011, 18:15

Since I "loosened" my purge valve and got it working again, my cel came back on with the PO443 purge valve circuit error. I connected my multimeter and rotated through the ignition switch... and stated the engine, I found no voltage at the purge valve term. When should this terminal be hot? I read about one fancy-pants fixing his own ECM circuit board... unless there is fire coming from the bad resistor, this would be stretching my ability. Any clues about where to find this missing voltage? BTW, my valve is still hot wire operational. 1999 S70 231K and lovin' it...... mostly

Post by **jmmxc** » 12 Dec 2011, 19:07

I have a hard time understanding what the problem is here.
Can you please be more elaborate in describing what the issue is, and why you are testing for purge valve voltage at the connector. What are you trying to find out? I have some experience with purge valve problems. Perhaps I can help.
Thanks,
jmmxc

Post by **Jack Rock** » 13 Dec 2011, 07:43

Your purge valve should only open when you're out driving. The ECU pulses the ground to open the valve at a rate designed not to effect the air fuel mixture, at least not any noticeable effect. This is necessary because the ECU is letting unmetered air and fuel (vapour) straight into the manifold from the canister so wide open would be undesireable.

0230683 · Post by **0230683** » 15 Dec 2011, 14:56

Sorry, I've been away. My purge valve was stuck in the closed position. I could not suck or blow through the valve. I have since "released" the valve and it now opens and closes when I put it on the bench andapply 12v to it . However, I still get a PO443 error "Evap system purge valve circuit" and I still don't know what this means or how to fixit. Do you think I have ECM trouble? BTW, thanks.