ACFT EQUIPMENT PROBLEM. HEADING DEVIATION.

Narrative

I WAS CLRED TO CREPE INTXN BY ATC WHEN ARRIVING AT THAT PT ACCORDING TO ONBOARD INSTRUMENTS I WAS AT CREPE INTXN. AT THAT TIME I WAS TOLD BY CENTER I WAS 4 MI LAST OF THAT POS. I THEN MADE A PROC TURN TO INTERCEPT THE LOC. UPON INTERCEPTING THE LOC I LEVELED AT 2300' MSL TO THE OM; I DID NOT RECEIVE A LIGHT OR HORN AT THE OM BUT WAS ABLE TO IDENT MY POS WITH A CROSS RADIAL FROM MORRO BAY VOR 355 DEG R; AFTER VERIFYING THAT I HAD PASSED THE MARKER I CONTINUED ON THE APCH WHEN I BROKE OUT OF THE CLOUDS AT 1100' MSL ACCORDING TO A CROSS REF FROM MORRO BAY VOR AND TIME I SHOULD HAVE BEEN AT THE MISSED APCH POINT & ABOUT 500' HIGH. AT THAT POINT I DID NOT SEE THE ARPT BUT I WAS VFR AND TRYING TO BE SAFE I ELECTED NOT MAKE A MISSED APCH BACK INTO THE CLOUDS FOR I HAD MADE THE APCH COUPLED TO THE AUTOPLT AND BY ALL INDICATIONS CENTERED NEEDLE AND CROSS RADIALS I SHOULD HAVE BEEN RIGHT AT THE ARPT. USING A BEARING FROM MORRO BAY I KNOW THAT I WAS PAST THE ARPT AT THIS TIME; SO I NOTIFIED THE TWR THAT I WAS MAKING A 180 DEG TURN AND TRACKING THE LOC BACK COURSE TO THE ARPT. UPON LOCATING THE FILED I WAS CLRED TO LAND. AFTER LNDG I WAS INSTRUCTED BY THE TWR TO CALL ZLA. I DID SO AT THAT TIME AND EXPLAINED TO THE CTLR WHAT HAD HAPPENED TO THE BEST OF MY KNOWLEDGE. AFTER THAT I WENT BACK TO THE ACFT & CHKED THE NAV EQUIP AND FOUND THAT THE #1 NAV RADIO WAS NOT GIVING ME AN ACCURATE READING AND THAT ON THE LOC APCH I WAS DRIFTING TO THE RIGHT WITH NO INDICATION OF THIS BY THE INSTRUMENTS. THIS HAS BEEN RPTED TO MAINT SO THAT IT CAN BE FIXED. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING: RPTR STATES EQUIP CHKED AFTER FLT AND FOUND NEEDLE WAS STICKING IN THE CENTERED POS; SO GAVE ERRONEOUS READING. RPTR THOUGHT HE WAS RIGHT ON LOC AND WAS DRIFTING OFF ALL THE TIME. HE WAS OBVIOUSLY AWARE OF SOMETHING WRONG; BUT DID NOT KNOW WHAT HAD CAUSED IT. BECAUSE HE WAS FAMILIAR WITH AREA AND COULD ORIENT HIMSELF AND IN THE INTEREST OF PAX SAFETY; HE CHOSE NOT TO ENTER CLOUDS AGAIN. TWR DID NOT HAVE ANY PROB; BUT CENTER WAS UPSET BECAUSE HE DID NOT CANCEL IFR. RPTR STATES HE WAS VERY BUSY ORIENTING HIMSELF AND RETURNING TO ARPT VFR. DID NOT THINK ABOUT CANCELLING. CENTER INDICATED WOULD BE IN TOUCH AND WOULD FILE VIOLATION. FAA REP FROM SAC HAS CALLED RPTR.