1998 Ford F-150 Now error 401 and 443

MRGEEV

MEMBER
1998 FORD F-150

Computer problem
1998 Ford F150 V8 Two Wheel Drive Automatic 124K miles

I was communicating with one of your car pros and the last thing he directed me to do was to check the resistance of the sensor, (purge valve) which was 35 ohms. Now I'm getting a total of 4 errors on my ODB II meter. Two for the 443 error and two for the 401 error, but both 443 errors are the same and so are the two 401 errors. The only thing I haven't checked is the pipe going back to the evaporator cans at the rear. I've checked the sensor mounted on the rear evaporator bracket and it reads the right resistance. Could it be my PCM gone crazy?

1 Reply

BMDOUBLE

MECHANIC
1,139 POSTS

I'LL ADDRESS THE P0401 FIRST. MONITOR THE DPFE VOLTAGE PID, SHOULD READ AROUND 1.00VOLTS. THEN GROUND THE EGR VACUUM REGULATOR AND LISTEN TO THE ENGINE IDLE DROP, IF IT DOESN'T THEN YOU HAVE CLOGGED PORTS AND YOU WILL HAVE TO REMOVED THE THROTTLE BODY AND EGR SPACER TO CLEAN. THE P0443, MAKE SURE YOU HAVE 12 VOLTS TO THE PURGE VALVE BUT IF YOU DON'T YOU WOULD HAVE MULTIPLE DTCS BECAUSE THIS POWER CIRCUIT GOES TO SEVERAL COMPONENTS SO THE FOCUS IS ON THE VALVE IF THERE ARE NO OTHER DTCS. LET US KNOW IF THIS HELPS OR HOW THE DIAG IS GOING.