ZPat96

So I had replaced my VAIS with a new one and the low circuit code came up P1800 thought it was maybe defective so I just put the old one back on and still have the same code... any thoughts on what I should be doing?

User1

So you got the code, replaced the solenoid, still had the code, put the old one back, and still have the code?

ZPat96

Yes I’m thinking maybe try replacing the MAF sensor as well?

ZPat96

Currently got 4 codes P0420 P0430 P0455 and P1800

User1

Looks like you need O2 sensors, fix an EVAP leak, and a solenoid. Are there one or two solenoids for 6th gen? I don't remember.

ZPat96

I think it’s just one haven’t found anymore haha

ZPat96

Any tips on how to fix emissions leak ? I’m thinking of replacing the vapor canister vent valve and the gas cap

User1

Gas caps are common failure points. If there are damaged components which need replaced, based upon visual inspection, I'd tend to those first then go from there.