Car stalls after fillup but it's not the fuel breather valve

[Bmwdoubles_]

Hi, all. I know this has been discussed a lot, and all the stories about stalling or bouncing idle or both after fill-up end in “replace your fuel breather valve.” I’ve done that, and it seemed to have improved the symptoms but not eliminated them. Most of the time, it’s a bouncy idle after filling up, but occasionally, it will stall. Additionally, after it stalls, the subsequent attempt to restart ends up in a crank that never starts the car. I have to turn the car off and give it a few seconds. Then the car will start.

Could it be that the charcoal canister is done? The lines are not holding pressure? By the way, I have a brand new LPFP and a brand new starter. Has anyone experienced something like this?

It throws no codes, and the car has 139k on it.

[Ajolives]

I went that route chasing a bouncing idle (not after fill up but after driving on highway for 15 miles). I replaced the fuel breather and it helped a bunch but didn’t eliminate the idle and sometimes stalling out.

I also couldn’t fill the tank about 1/2 the time I pulled up to the pump, it would click off anywhere between 1/2 tank to 3/4 tank full.

I replaced the charcoal canister, not with electronics, I bought just the canister and transferred over all the pieces. I also replaced the breather line with built in filter. It takes gas now but the idle stumble is still barely there but much reduced.

I was also running a cracked (Turner) exhaust and switching back to stock helped a bunch too.

I’m convinced it’s a vaccuum issue but haven’t found where exactly. It’s most troublesome for me 80-90 degree ambient so when temps get back there I’m gonna pick up where I left off. Hope this helped in any way.

[Bmwdoubles_]

Originally Posted by Ajolives

I went that route chasing a bouncing idle (not after fill up but after driving on highway for 15 miles). I replaced the fuel breather and it helped a bunch but didn’t eliminate the idle and sometimes stalling out.

I also couldn’t fill the tank about 1/2 the time I pulled up to the pump, it would click off anywhere between 1/2 tank to 3/4 tank full.

I replaced the charcoal canister, not with electronics, I bought just the canister and transferred over all the pieces. I also replaced the breather line with built in filter. It takes gas now but the idle stumble is still barely there but much reduced.

I was also running a cracked (Turner) exhaust and switching back to stock helped a bunch too.

I’m convinced it’s a vaccuum issue but haven’t found where exactly. It’s most troublesome for me 80-90 degree ambient so when temps get back there I’m gonna pick up where I left off. Hope this helped in any way.

I was thinking it could be with the charcoal canister, but the inline fuel filter I’m not familiar with. I’ll have to look that up. It does kinda act like a vacuum leak I’ll have to smoke test that too. I appreciate the leads.