Changing connector for VIAS Control Solenoid Valve
This is a short article on what to do if your p1800 SES does not go away. First of all, if you replaced the valve and you still have p1800 SES, check all wiring around the sensor. In my case, I had a faulty connector. The wires came off and I was not able to reattach them.
I ordered the connector. Now, if you want to get a connector yourself, there are only several ways to go. You can look on ebay, but you will not find a single one because it's not a common practice to replace a single connector. You can find a seller that is parting out Maxima or i35 and ask them if they'll sell you the connector. Another good place to find one is through forums. I used maxima forums and found a seller there. He sold me the connector for about $10-$15 with wires attached. Keep in mind that you want a connector with two wires attached to it and the wire should be about foot long.
Now what you need to do is simply cut off the original VIAS connector and attach the one you purchased. The connector or the wire color might be different. Just make sure the wires get where they supposed to go.
To connect the wires to each other, you can use connectors or just tape them. I used Posi connectors I had and then zip tied everything to existing wires. For safety, you can also use waterproof connectors and find another connectors. Tape can be used as well, but I am not sure how long the tape will stay on the wires. Use any of these options at your own risk.
After wiring is done, connect two hoses where they belong (if you are replacing the valve as well). I had to use pliers to remove the hose from existing VIAS sensor. You can also buy new hose if needed as they should be cheap in a local auto parts store.
After everything is done, time to erase your SES light. If there is another issue, keep researching online. Don't forget to celebrate if SES is gone for good.