Manager Forum

Have a 2000 Chevy pickup that is kicking me while i am down. It has a code P0446 and at frist we put on a vent vale kit from napa but then it came right back in a few days latter. So got another one and that is when i seen in my testing what it was doing. It will close but will not reopen like it should. If i tap on it it will pop open. I have unpluged and pulled hoses off and still will not reopen. Have checked power and ground and when i comand it to close it does great but just open it will not do some times. So we put one on from gm and it did the same thing and so i sprayed a little lube in it and it seemed to work great. Put then he came and picked up the truck and he called when he got a little out of town and said the light is back on. Please tell me then some one has seen this before.. The one on it now is from gm. it does have the remout filter...

thanks for any help

Never seen it but the most common thing we see with that code is the pressure sensor

Yea i thought about that and it looks good when i have looked at it. I just dont get why this valve will not open after the ground is taken away. Everything tells me then it is the valve but i just cant see getting 3 bad ones at the same time doing the same thing. And one was a gm one.. Belive the truck is coming in again next week so i will look at that sensor again to see what it is saying. At this point i will try about anything...

Never had it happen so I don't know. Is dirt getting into the valve and causing them to stick?

No even put the filter where the TSB said to. The last time it was here is when i really seen what it was doing

Maybe test the voltage drop across the ground. Or a low ohms/high resolution test on that circuit. If you are applying ground for the test and it works then maybe there is excessive resistance in that circuit ?

bad elec connection at valve? What if you unplug it while valve is stuck

If i unpluge it it is still stuck. The computer sends ground to it to close it and then takes it away to open. If i tap on it it will open up. That is why the last time i sparyed just a little wd-40 in it to see if that would help free it up. It seemed to be working untill i guess he got a few miles out of town. I layed under that truck and made it work at least 30 times and it worked great..