clicking from under the hood
 

I HAVE A 2000 E-150 VAN WITH A 4.2 V-6, IT STARTED CLICKING A FEW MONTHS AGO, AND ABOUT TWO WEEKS AGO THE POWER STEERING PUMP PULLEY DISENGAGED, IT WAS MADE OF FIBER,SO CHECK YOUR PULLEYS CLOSELY, THE REPLACEMENT PULLEY WAS MADE OF STEEL, IS THAT STRANGE, ALSO THE CHECK ENGINE LIGHT KEEPS COMING ON, REPLACEDEVERYTHINGONTHEMOTOR,O2,COIL,WIRES,PVC,HOS ES,ELBOWS,PLUGS,CHECKED FOR VAC LEAKS,FOUND A WEB SITE FOR DEALER,IT SAID AS THE CAR GETS OLDER, THE COMPUTER STORES FUEL TRIM CORRECTIONS,WHEN IT CHANGES BEYOND LIMITS, THE FUEL STRATEGY IS NO LONGER ALLOWED
SO I GUESS YOU HAVE TO TAKE YOUR VEHICLE IN TO THE DEALER TO GET IT RESET,HOWCONVENIENT.FORGOT IT HASCODES PO171 AND PO174
BANK 1&2 LEAN

I TOOK THE VAN TO A DEALER IN SOUTHERN ILLINIOS, AND THEY PULLED OFF THE COVER OVER THEMOTOR AND FOUND 5 OF THE 6 EGR PORTS BLOCKED, WHICH CAUSED CODE PO171 ANDPO174,THEY SAID IT WAS FROM LEAVING THE ENGINE SET AND IDLE COST ME $300.00 NOT BADONE HINT MY GAS KEEP GET BETTER AS THE PORT STOPPED UP BACK TO 16 MPG,NO MORE CODES.

RE: clicking from under the hood
 

Yes, the PCM learns the fuel trims over time, when you make repairs you will need to disconnect the battery for a few minutes to clear the memory. This engine has also had intake gasket problems.