Ive searched and fumbled over this for weeks now. Im getting code p0441 Evap Emissions System no flow(During Purge). What's wierd is that im only getting it with my tuned PCM. With the OEM pcm i can't get the code to come back.

Well, after searching, I found somthing interesting. When I fill up my car with gas, sometimes the pump shuts off early. Sometimes I can only squeeze the handle halfway to fill it up. I found in a search that it might be related to the p0441 code? Like, its not letting the gas tank relieve pressure which is why the pump is shutting off...? But like I said, I can't get the code to come on with my OEM pcm at all.

Ideas please?