Problem with an A.O. Smith water heater

IM HAVING THE SAME PROBLEMS. BEEN WORKING ON IT FOR 3 MONTHS NOW. I HOPE THAT I DO NOT JINKS MYSELF! LONG STORY,SHORT. THE LAST ATTEMPT THAT I MADE WAS TO SWAB THE INTAKE AND THE EXHAUST PIPES. MY PIPES HAD SCREENS IN THEM. WHEN I SWABBED, I PULLED OUT A COKE BOTTLE AND A WASP NEST. I THOUGHT, THIS IS IT! CUT IT ON AND FIRED UP AND RAN FOR 2 DAYS. CUSTOMER CALLS, SAYS THAT ITS OUT AGAIN.BEFORE THE SWABBING, I HAD REPLACED EVERY PART AN THE HEATER EVEN IF IT DIDNT HAVE ANYTHING TO DO WITH THE PROBLEM.BY THIS TIME IM LOOSING FAITH IN MYSELF. I RESET IT ONCE MORE AND LEFT TO DIG ON THE WEB TO FIND SOMEONE WITH THE SAME CRAZY ISSUES.AFTER RESETTING IT AND LEAVING, IT RAN WITH NO PROBLEMS. I WENT BACK BY TO JUST CHECK ON IT. WHILE I WAS THERE,I THOUGHT THAT I WOULD ADD MORE GAS TO THE HEATER BY ADJUSTING THE REGULATOR. 2 HOURS AFTER I LEFT,THE CALL CAME IN, IT OUT AGAIN! THIS WAS NO COINCIDENCE. THIS LEAD ME TO POINT AT THE REGULATOR. I WENT THE NEXT DAY TO REPLACE THE REGULATOR AND SO FAR SO GOOD! THIS WAS 2 WEEKS AGO AND ITS WORKING FINE FOR NOW. IM STILL NOT CONVINCED THAT THIS WAS THE PROBLEM BUT!!!!!!!!!!!!! IF THIS WORKS FOR 30 DAYS , THEN I WILL BELIEVE IT. THE REGULATOR IS THE LAST THING THAT I WOULD SUSPECT AS THE PROBLEM.I NOTICE THAT YOUR PROBLEM LIKE THIS WAS A FEW YEARS AGO, DID YOU EVER FIGURE YOURS OUT?

CAPS!!!