well basically i tested the old and new purge solenoid from a cold start and when i did this the old one was pulling vaccum and the new one wasnt. then after driving around for a while it was pulling vaccum so i have a good feeling that is all it was and the codes need to clear. i have the old switch in my hands now and when sucking on the engine side it flows right in and right out, but when i plug up the return line(bottom line with the other switch) it holds sealed. is it bad if its free flowing like i mentioned or not because it holds when i block the other end? hope this is good information, im trying to be very informative.

 

I believe the vacuum switch (#11 in the illustration above) should be open through the in/out lines all the time. but the purge valve #7 should be sealed internally (untill the computer turns it on/open) all the time w/the key off or valve unplugged. so #7 is the one you need to try blowing through from the engine side though. the valve might not seal completly from the other side.

 

ok, well the purge solenoid(number 7) was completely open, blow through it or suck air out of it either way, which leads me to beleive that it was in fact bad and i just tested the new one while it was actually doing its job, so i just need to wait until the codes clear or maybe ill pull the battery off for a while. we'll see what happens.thanks

 

i pulled the battery off and the light was off for a few days, then it came on last night. i really thought the problem was fixed, but now i dont know what it could be. that flow detector switch maybe? i was planning on doign my headers and then getting the EGR/AIR tuned out of the computer and maybe just have the guy at the place check out the EVAP problem too. any thoughts?

 

Make sure you didn't mix up the hoses on the solenoid its designed to work one direction only

 

i put it on correctly. i didnt double check it, but im almost 99.9% positive its on correctly, there was a time where i tried it and it didnt suck on my finger, and the new one wont let me suck freely on the engine side, but the old one does.

 

Id still try the switch, cause its soo cheap. if that doesnt do it, take it in.

 

alright im gonna buy a new one tomorrow and put it in, then if thats not it im gonna have the guy whos tuning out my EGR/AIR take a look at it after i install my longtubes. thanks for the help

 

the part is on order from GM. i talked to the guys at the dealer and they said for 100 bucks they can tell me whats wrong, and now im finding out if the guy whos gonna tune it wil be able to help me or not. idk what im gonna do yet. put the new switch in on tuesday and see if that helps. thats the last thing im buying for it though until i know whats up.

 

if your charcoal canister is failing, it may have introduced particles of charcoal into the pulge/vapor line, which in turn can jam the purge valve open, you should make sure the line is clean inside by pulling the line off at the canister and the valve, then blowing it out with air, to find particles, have someone hold the end in a rag or something to collect the particles

 

that does actually make a lot of sense, because now it seems like the new one is stuck open, and when i sucked on the old one to show the dealer how it was stuck i got a lot of really nasty charcoal and "grits" in my mouth. i know where about the canister is but how do i actually get to it? ive never had to deal with one before. thanks for the good alternate advice Dave.

 

That's the same problem my car had. The cannister was shot and I sucked a mouthfull of charcoal bits up. I have a new GM cannister if you find you need one. It's a little bit of a pain in the butt getting the cannister out.

 

hmm.... well i was just working on the car for about an hour or so, cleaning and checking out the lines to the canister. i saw it back in the 1/4 panel after i got the plastic shroud off the filler neck. i assum the canister slips out through this hole and is just a pain getting at it or do i have to drop the tank and that? well anyways i took off the line from the canister to the system under the hood and blew through it with a compressor. i took everything apart from the line bundled in the big fuel line thing to where it goes into the throttle body and then like i said blew out the line from the canister. i was by myself and i blew through it a LOT. maybe the canister is bad, but idk. besides the purge solenoid and that flow detector switch is there anything else that would go bad causing a SES light or is it prolly that canister? any help is always great. Jeff, im gonna look into it more but how much would u want for that shipped to chicago?

 

or you could just have the evap system deleted when you have your other stuff deleted.

 

I think you want to keep the EVAP purge system so you don't get that gas fume smell from tank pressure venting to the atmosphere. You get to the cannister by removing that plastic panel from up inside the rear wheelwell. Don't mess with the fuel filler neck area, that has nothing to do with the cannister. I think there are 1 or 2 bolts holding the plastic panel up and maybe 2-3 little plastic clips. Once you pull that out of the way you can get to the cannister and lines easier. But getting the cannister off it's bracket can be tricky. Slide it down as far as it will go and then you can pry it off. I think I paid around $50 for the cannister so I'd like to get back as close to that as possible. I'd probably sell it for $45 shipped.