problems starting only after adding gas no other time and running rough

[mykelp]

My 06 mazda 6 starts 100% of the time on the first try except every single time I add fuel it takes a few times excessive cranking before it starts it also runs lean and shows codes for gross evaporative leak and a code for one of the banks/sensors lean condition I've smoke tested the evap system couldn't find a leak I know there's gotta be a leak somewhere right its driving me nuts cause I'm thinking ok doesn't start only when addind fuel so when I add fuel I'm releasing the fuel tank pressure but shouldn't the fuel line hold pressure still could fuel pump be failing but again only has problems first start after fueling and doesn't happen again untill refueling so I'm doubtful its the pump maybe purge solinoid but I think it would not start up on cold starts so why only after adding fuel possibly hopefully just a evap line puncture I missed cause that makes sense and reading codes for gross evap leak and bank one running lean please someone make me understand I hopefully think I'm just not seeing the evap leak causing all this help

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[virgin1]

I'm not sure what the problem is, but I would start small.
First have the fuel cap checked.
Second, see if the evaporative fuel return check valve (re: a small plastic piece that in my 3 series is in the front of the engine, nearly dead center, and has an attached plastic hose) is operating (e.g. not sticking.) Often these little buggers can cause all kinds of weird problems, and often the fix is simply tapping it with the handle of a screwdriver to get it moving again.
Then worry about fuel pumps, and other big-buck stuff..... You'd be surprised. It's often the little things.

[tanprotege]

I agree with Virgin1. It's often the little things.

the lean condition may be independent from the EVAP leak. You should check the intake side for vacuum leaks as well.

[Brittanyyy]

I have the same issue with my '07 Mazda 3. Did this help? I've replaced the gas cap and 02 sensor because those were the codes it was reading, neither helped. The problem at the tank continues to get worse each fill up.

[UseYourNoggin]

Try the purge valve solenoid. It's down at bottom of engine firewall on passenger side on Mazda 6. It's not hard to install at the shop. Parts and labor under $100 (depending on your year and style of valve).
P0443 trouble code symptoms could be just an malfunction indicator lamp (MIL) illumination. There may be no drivability problems at all. But, it's also possible to have a lean condition or a rough running engine if the purge valve is stuck open. Usually though, these symptoms are accompanied by other EVAP codes. Another symptom may be excessive pressure in the gas tank (after fillup!!) in the form of a "whooshing" sound when the cap is removed, indicating a purge valve that isn't working at all or stuck closed.