JVinOlathe
Active Member
1999 Expedition 5.4L Eddie Bauer, 145,000 miles
I have been having the P0171 and P0174 codes for while now. I checked and cleaned the MAF with MAF cleaner, replaced the PCV valve and one hose that appeared frayed but the codes come back. Overall the truck worked OK although the fuel efficiency was lower. I was just waiting for available time to get it checked by a mechanic since my knowledge is limited.
A few days ago, the truck started idling slower and some times it would die at a traffic light but started right back up with no problems. Sometime I would just give it a little gas when stopped at a light and the truck would do OK.
Yesterday it died at a traffic light and when I restarted , put it on gear and gave it gas the truck would shake and fishtail when moving forward. Weirdest thing. I was not too far from home so I limped it there at 10 MPH.
Today I run my Acton Code reader and found the following codes:
P0442 - Evaporative emission system leak detected - pending
P0174 - Bank 3 system too lean - confirmed
P0171 - Bank 2 system too lean - confirmed
P1151 - Heated Oxygen Sensor Bank 2 Sensor 1 switch point indicates lean - confirmed
P1131 - Lack of heated oxygen sensor (bank 1 sensor1) switch, indicated lean - confirmed
My limited research indicates it could be a bad purge valve or a faulty PCM.
Would any of these codes cause the truck to shake and fishtail when moving forward othre than very slowly?
Would a faulty PCM cause this or am I looking at a drive train issue?
The front brake pads and rotors were replaced about 500 miles ago but do not seem to be the issue. would seized brake cause this issue? There does not appear to be any smell so nothing seem to be binding, as far as I can tell. When idling in park the engine is a little rough and sputters some but not terribly so,
Really weird issue. any help you can provide would be greatly appreciated as I need to decide if the repairs are worth it for a truck this old but in otherwise pretty good shape.
I have been having the P0171 and P0174 codes for while now. I checked and cleaned the MAF with MAF cleaner, replaced the PCV valve and one hose that appeared frayed but the codes come back. Overall the truck worked OK although the fuel efficiency was lower. I was just waiting for available time to get it checked by a mechanic since my knowledge is limited.
A few days ago, the truck started idling slower and some times it would die at a traffic light but started right back up with no problems. Sometime I would just give it a little gas when stopped at a light and the truck would do OK.
Yesterday it died at a traffic light and when I restarted , put it on gear and gave it gas the truck would shake and fishtail when moving forward. Weirdest thing. I was not too far from home so I limped it there at 10 MPH.
Today I run my Acton Code reader and found the following codes:
P0442 - Evaporative emission system leak detected - pending
P0174 - Bank 3 system too lean - confirmed
P0171 - Bank 2 system too lean - confirmed
P1151 - Heated Oxygen Sensor Bank 2 Sensor 1 switch point indicates lean - confirmed
P1131 - Lack of heated oxygen sensor (bank 1 sensor1) switch, indicated lean - confirmed
My limited research indicates it could be a bad purge valve or a faulty PCM.
Would any of these codes cause the truck to shake and fishtail when moving forward othre than very slowly?
Would a faulty PCM cause this or am I looking at a drive train issue?
The front brake pads and rotors were replaced about 500 miles ago but do not seem to be the issue. would seized brake cause this issue? There does not appear to be any smell so nothing seem to be binding, as far as I can tell. When idling in park the engine is a little rough and sputters some but not terribly so,
Really weird issue. any help you can provide would be greatly appreciated as I need to decide if the repairs are worth it for a truck this old but in otherwise pretty good shape.