Stupid me, I deleted a code on my 97 without making sure what it was. It said something about low flow purge something but I accidently deleted it after just glancing at it. All the vac lines from the fuel tank to the purge canister seem to be in good shape and not leaking but I do have a small pin hole in the bottom of the gas tank (not enough to actually drip, just enough to keep the area moist with gas). I filled it up for the first time ever yesterday as I was going on a 500 mile road trip and the CEL came on when it was down to a quarter tank. I'm not really sure the pinhole is the problem but any input would be helpfull

 

It hasn't come back on but I'm still curious if anyone has any ideas

 

All I can find for this in my FSM (for a 2000 xj) , P-0441 evap purge flow monitor failure. Things to try, remove Purge Soleniod and tap the ports against something clean,and solid, to check for debris. Inspect all vacum hose's for proper routing and for pinched or plugged hose's from engine to solenoid to the gas tank.
Next replace Purge solenoid,and a Purge Vapors Test.Thats it. good luck.