I am new to the F150 forum and I have a question concerning my 1998 Ford Expedition Eddie Bauer with 5.4 liter engine

I have the following codes: all of them at once last time checked

P0171
P0174
P0156
P1131
P0136
P1151

Am I to interpret this as a need to replace all four of my O2 sensors?

My mileage on my Expedition is at 87,000 and I have researched this forum and found excellent info but I haven't found anyone with these codes all at once. As an FYI my truck hesitates, has problems with idling and has shut down completely at times so what do you guys think?

 

Hi 6ft

Welcome to the forum!
I'm sure someone else may have more info but, I believe the P0171/74 codes
refer to "system lean, bank #1 and #2." I would try checking the MAF (Mass
Air Flow) sensor. It could be dirty or bad. It should be located in the air intake
tube between the air filter box and intake manifold. I'm not sure about the rest of the codes.
(they could be related to the first two).
You can also check: www.obd-codes.com and see about the other codes.

Hopefully this helps.

 

Anybody else with input on the forum? I do have good news I got those codes down to 4

P0171
P0174
P0401
P0136

I have replaced the EGR Valve, the DPTE sensor the two hoses that stem from it which on of them was dry rotted/bad I know that was a vaccum leak.

I will get the codes cleared again tommorow with a scan tool and see how that goes but for some odd reason I think the vacum leak from the one iddy biddy hose was the nightmare cause all those multiple codes!!!!

 

Now follow the PCV line from the valve cover back to the back of the engine and you will probably find another bad rubber connection.

 

How hard and how long did it take for you to replace the EGR Valve???
I might have to do the same.

 

Suave, the EGR vavle wasn't 2 hard but I did require some assistance from a friend. I will say though I now think it may not have been necessary.

I will look into the PVC hose, valve replacement!!! I still have these codes going on and had them cleared last night I will get them reread today.

Hey will that PVC vaccum leak cause such a rough riding condition yall?

Also my EXPY has over 80K no CEL or anything isn't the O2 sensors due for replacement all 4?(sigh)

anybody please chime in.

 

I had a 97 expy with the 5.4L. Same problems, 140K miles. I changed out the EGR and DPTE, and several rubber hoses. No other problems after that. Good luck

 

These pictures won't last long, so you better copy them to your computer. Alldata doesn't look kindly upon hotlinking their pictures.

P0171, P0174


P0401


P0136


That should help you solve whatever you need.