Strange idle upon fueling up 2015z
 

Hey guys, freaking out here. Every blue moon when I fill up my Z the car shakes upon start up, the tachometer jumps up and then everything is normal. Doesn't seem to happen everytime and the car is normal after the initial shake. it's done this twice before but this time it was a huge jump on the tacho upon idle and jumped up twice. What is causing this? Fuel pump? Choke? Im 100% sure im using the right gas. Seems to happen almost every time I fill up at half a tank

It's not the gas - the new stuff takes a while to get to the engine. I suspect an emissions/vapor problem.

is the car stock?

the gas tank has lines going to a charcoal/evap canister to capture evaporating fuel vapors when the car is off and a purge valve to release the vapors to be burned by the engine when the car is at operating temparture

you have regularly topped off your gas tank and have flooded the charcoal canister and broken the purge valve. you are now sending fuel to the engine insted of vapors and flooding the engine upon startup. this is not happen during cold startup , the valve only opens when the coolant temp is above x and car r is moving not at 0 mph UNLESS afteryou refuel because the onboard refuelding vapor revovery system tells it to open when you start becus it sensed the pressure in the fuel tank!

your charcoal can is full of fuel becus you overfilled gas!

when the onboard refueling fuel vaper recovery system tells it to open after you refuel you are sending gas insted of vapor becus your charcoil can is full of fuel!!!

Seems like an amateur mistake, I always thought it was good nature to top off. Is this detrimental? Does it require a fix? If so what are we looking at here? Thanks in adavance, love you guys!

Edit: Car is stock

Try to use the fuel to over 1/4,just top up to 7/8 full,see will this happen again..Then you will know the answer.

Thanks I'll give it a shot.

Such a weird problem guess I wont be completely "topping" off my car anymore

1st click off, that's it, don't try to get more in....

Never?
 

Never heard of this! For ANY car/truck.

Whoops, lol I fill mine up usually at 1/3 left, but I top it off and pop it a couple times because every fill up when I've had it damn near empty, itll leave a dot off, so I figure there about a half gallon + that we have to work with.
It does make sense in a way, but never heard it being an issue with the Z's and we have been going off the premise of fill up at 1/2 tank to prevent fuel starvation

I'd research it a bunch and ask your mechanics you use most often. That way you see prices and get a start of what else could need to be replaced or fixed based on this part failing.
IF so and it is a problem stemmer and with how our Z's love that fuel starvation on right turns below a half tank, plus not being able to fill it up all the way seems like a hassle. Just rip the whole fuel system out and replace it with parts that actually work correctly. Friggin Nisssan..

His charcoal can is full of fuel! Its too late to not overfill the gas tank, he already did and the gas went into the charcoal can and it is probably leaking charcoal into the evap lines! replace your charcoal can and dont overfill your gas tank!!!

once the charcoal gets wet with fuel it cant be reactivated to store vapors! you have to replace the can or drill a hole and empty the charcoal and refill with new charcoal and seal the hole!