P0441 Purge Vlv...can I check it?

[Dwpc]

My '06 Turbo 955 is throwing a P0441 code and also has had two instances of hard warm start with no code showing. Is there a way to test or check that the valve is bad and a replacement will fix the hard starts before buying a replacement?

[Casey at Pelican Parts]

Originally Posted by Dwpc

My '06 Turbo 955 is throwing a P0441 code and also has had two instances of hard warm start with no code showing. Is there a way to test or check that the valve is bad and a replacement will fix the hard starts before buying a replacement?

Best way to do it is with the scan tool, go to drive links, then activate the purge valve. Usually you will not hear them clicking when they're bad. If you don't have access to a scan tool, you can simply power the valve by adding B+ to one terminal and then ground to the other. Then when connecting and disconnecting the ground you should hear/feel a click in the valve. If it does not click you need to replace the valve. If it DOES click you should still test it by blowing or sucking on the pipe going in to the valve. Un powered it should be open (from memory) and powered it should close and be very hard to blow through. If it is easy to blow through powered or not then the valve is bad. If it is hard to blow through regardless of it being powered or not then it is bad.

[Dwpc]

Originally Posted by Casey at Pelican Parts

Best way to do it is with the scan tool, go to drive links, then activate the purge valve... not then it is bad.

Thanks for the thorough explanation. I have only a generic OBDII scanner, but will check the valve with jumpers. Can I just take B+ from the charging post under the hood? The code appeared when driving for long periods on the interstate, but hasn't reappeared since we returned from our trip, so the purge valve may fail only when it gets really heat soaked.

I'm still not clear whether the valve caused the hard warm starts with no CEL. Does create a vacuum leak when it sticks open?

[Casey at Pelican Parts]

Originally Posted by Dwpc

Can I just take B+ from the charging post under the hood?

I'm still not clear whether the valve caused the hard warm starts with no CEL. Does create a vacuum leak when it sticks open?

Yes, use the B+ post in the engine compartment, it's a good idea to use a fused jumper wire on the B+ side just in case you touch your GND lead when testing. It will save your jumper wire from melt down!

As for the hot start, I have seen in MANY cases, a purge valve cause a hot start issue. It is basically a vacuum leak which can cause the engine to have either a lean OR a rich condition. Because it is pulling from the charcoal canister...in MOST cases the charcoal canister will be loaded with fuel vapors, and when the valve is stuck open those vapors will be sucked in to the engine, and not be metered by the DME, which would definitely cause a hot start issue. On cold starts you probably would not notice very much of a difference because the engine needs to run "richer."


Make sense?

[Dwpc]

Yes it makes sense. Thanks.