P0402 code but....
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Junior Member
Joined: Jun 2020
Posts: 15
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P0402 code but....
I’ve got a 2008 4.2L F15@ around 180k miles.
brand new motor craft EGR system (has built in DPFE SENSOR), rebuilt throttle body, new PCV valve. The EGR ports were vacuumed out when it was replaced....
its been running rough during idle, misfiring occasionally, has 3 O2 sensor codes (Bank1 sensor 1 lean, bank 2 sensor 2 Lean AND rich (wth!?!) and now there is a P0402 code. I doubt it it’s the new FoMoCo EGR or throttle body(with all new gaskets)
this has been an ongoing issue that’s led to new EVAP purge solenoid and canister solenoid, new driver module, fuel pump, battery.
my short term fuel trimS are like -5.4%
HELP a girl out here y’all? This truck just keeps running rough and I am trying my best to diagnose and fix issues.
why am I getting an EGR code? Could it be faulty Oxygen sensors causing this? Could it be a Wiring/electrical issue or PCM issue?
brand new motor craft EGR system (has built in DPFE SENSOR), rebuilt throttle body, new PCV valve. The EGR ports were vacuumed out when it was replaced....
its been running rough during idle, misfiring occasionally, has 3 O2 sensor codes (Bank1 sensor 1 lean, bank 2 sensor 2 Lean AND rich (wth!?!) and now there is a P0402 code. I doubt it it’s the new FoMoCo EGR or throttle body(with all new gaskets)
this has been an ongoing issue that’s led to new EVAP purge solenoid and canister solenoid, new driver module, fuel pump, battery.
my short term fuel trimS are like -5.4%
HELP a girl out here y’all? This truck just keeps running rough and I am trying my best to diagnose and fix issues.
why am I getting an EGR code? Could it be faulty Oxygen sensors causing this? Could it be a Wiring/electrical issue or PCM issue?
Old school
Joined: Mar 2020
Posts: 154
Likes: 55
From: PA
Casey,
With 200K miles, I would be looking for a vacuum leak due to old hoses. Ozone under the hood makes the rubber brittle. On my 68 Goat, I just purchased rolls of tubing from auto parts store and replaced one-by-one to avoid mistakes. If you don't want to go that route, cut off 1/2' off all the ends to get rid of splits and swollen ends. Verify there are no leaks while running by passing an unlit propane torch at suspect connections. RPM increase or smoother running is the clue. Not saying this is the only thing to check, but it is cheap preventive maint,
45K40
With 200K miles, I would be looking for a vacuum leak due to old hoses. Ozone under the hood makes the rubber brittle. On my 68 Goat, I just purchased rolls of tubing from auto parts store and replaced one-by-one to avoid mistakes. If you don't want to go that route, cut off 1/2' off all the ends to get rid of splits and swollen ends. Verify there are no leaks while running by passing an unlit propane torch at suspect connections. RPM increase or smoother running is the clue. Not saying this is the only thing to check, but it is cheap preventive maint,
45K40