Mechanics

FORD EXPEDITION SENSOR PROBLEM

2003 Ford Expedition • 195,000 miles

Had just driven about 100 miles. Five to ten minutes later was going to pull the vehicle out of the garage. When I went to start it, it sort of sputtered for a few seconds and then would just not do anything. It cranks over but sounds like it won't fire or it's not getting fuel. Checked, I think all the relevant fuses and the emergency fuel shut off. Didn't find any problem there. I know I also need to change a sensor or some related part in the charcoal recapture system. It has been running fine though even with that indication. Where should I start?
Avatar
Guest
March 27, 2013.



IS THE CHECK ENGINE LIGHT ON?

LET'S START WITH THE CHECK ENGINE LIGHT

IT CAN BE ON FOR MANY (HUNDRED OR MORE) REASONS

SOME ARE NOT SERIOUS---OTHERS ARE

GET IT CODED----YOU MAY HAVE A SENSOR NOT WORKING

WE GOT TWO "LOOPS"---"OPEN" AND "CLOSED"

OPEN MEANS THE SENSORS ARE GIVING THE COMPUTER "REAL TIME" INFO, EXAMPLE: O2 SENSOR IS TELLING THE COMPUTER THE OXYGEN CONTENT IN THE EXHAUST SO IT CAN ADJUST THE INJECTORS TO GET THE MOST EFFICIENT "BURN" POSSIBLE

BEING THAT IT TAKES A BIT FOR THE O2 TO WARM UP TO "TRANSMIT" INFO. HOW DOES THE ENGINE RUN?

THE ENGINE RUNS "CLOSED LOOP"---WHICH MEANS THE COMPUTER HAS "PRESET" VALUES PROGRAMMED INTO IT--IT RUNS OFF OF THEM, UNTIL ALL SENSORS COME ON-LINE. CLOSED LOOP SORTA MEANS, "FED FALSE INFO", THAT WILL MAKE THE ENGINE RUN---THIS "LOOP" IS NOT EFFICIENT, USUALLY YOU WILL NOTICE IT RUNS RICH--MPG GOES DOWN!

THIS IS NOT ONLY TRUE FOR THE O2 SENSORS, BUT OTHER SENSORS NOT WORKING WILL CAUSE THIS (STAYING IN CLOSED LOOP)---CLOSED LOOP IS BASICALLY "DEFAULT"

I'M NOT GREAT ON NEWER VEHICLES, IMMA JEEP CJ KINDA GUY '40-'86 IS WHAT I KNOW THE BEST. BEFORE COMPUTERS!

MANY POPULAR AUTO PARTS STORES WILL "CODE YOU" FOR FREE

WRITE DOWN THE #s--THEY WILL BE IN A FORMAT SORTA LIKE "P0345" OR ANOTHER MADE UP EXAMPLE IS "PO445"

JUST 'CAUSE "AUTO PARTS MAN" SAYS, "IT'S YOUR EGR"----HE MAY BE WRONG---CHECK FOR YOURSELF!)---YOU NEED THE EXACT CODE NUMBER!

TAKE THE EXACT NUMBER TO "GOOGLE"----TYPE IN "OBD-CODES PO445" (WHATEVER YOUR CODES ARE---YOU MAY HAVE SEVERAL---DO THEM ONE AT A TIME ON YOUR GOOGLE SEARCH)

I USUALLY GO TO

OBD-CODES. COM/ AFTER THE "/" INSTALL YOUR CODE (SUBMIT ONE AT A TIME) THIS SITE IS GOOD ABOUT EXPLAINING WHY THE CODE SHOWED UP----THEN IT USUALLY GIVES YOU "POSSIBLE CAUSES". AND BEST OF ALL, "POSSIBLE SOLUTIONS"

AN EXAMPLE IS: OBD-CODES. COM/P0442

IF IT WON'T MOVE, THE OLE "OBD II" SYSTEM IS SORTA HERE TO STAY (FOR YOUR CAR ANYWAY), MAYBE YOU AND YOUR BUDDIES COULD CHIP IN AND GET ONE. OR YOU COULD RENT IT TO THEM TO "RECOUP" YOUR COST LATER!

NO NEED TO GET ANYTHING REAL FANCY ALL YOU NEED IS IT TO DISPLAY THE CODE NUMBERS---THE FANCY ONES, SHOW THE "CODE MEANING", IF YOU ARE NOT FAMILIAR AND EXPERIENCED IN THE INTERPRETATION. YOU ARE GONNA HAVE TO GO TO THE LINK I MENTIONED ANYWAY. THESE SCANNERS DO NOT "TELL YOU WHAT TO FIX". THEY ONLY TELL YOU WHAT SYSTEM WAS AFFECTED

YOU COULD HAVE OTHER PROBLEMS LIKE A BAD FUEL PUMP, FUSES, FUSIBLE LINKS, SENSORS, BROKE WIRES, THE LIST GOES ON. MORE INVOLVED TESTING MAY BE NECESSARY

CODING SHOULD BE YOUR 1ST STEP

THE MEDIC


Tiny
CJ MEDEVAC
Apr 1, 2013.