P0449 help!

My 99 Venture has the dreaded P0449 EVAP Control Circuit malfunction. It's been at my mechanic for 3 days last week, and now 3 days this week. He's replaced the Vent Control valve solenoid, cleaned the connector for it, checked the wires from it to the junction box that runs thru the floor under the drivers seat. He thinks the PCM is not sending a ground signal to the valve to open it, so he's thinking the PCM needs to be replaced. The van has 190K on it, and I'm not happy about dumping another $300 into it just for a PCM so I can pass inspection. Anyone have any other ideas?

get the PCM flashed for no Evap......

lesterl - thx for the reply. Who does that? the dealer? What does that do, reprogram the PCM?

Yeah, dealer WONT delete the code, you will have to use a company that flashes for performance/ preference etc. Like if you make non stock engine mods i.e. cam/ exhaust/ etc.

Now, if your mechanic doesnt KNOW if its getting a ground signal out, I would find another mechanic, all you do is put a meter or probe to the pin on the PCM, and have your scan tool command the valve open. You should see a result. I think even turning the key to run will cause a quick self test of said circuits so you wouldnt even really need a scan tool IIRC.

Just a follow up. After about 2-3 weeks of on and off at the shop, and after I purchased a replacement (used, programmed) PCM, my problem ended up being a wire coming from that dreaded junction box in the floor behind the drivers seat. SES light is out, inpection sticker is all set!

Forgot about that darned junction block!!!!! Sorry we missed it..... Glad you got it tho..... :-)