problems with 1997 expedition.

[jlo82585]

hey y'all, so like I said in a prior post my lil' sisters 2002 XLT expedition got killed by a ford focus that thought 80mph was a good traveling speed in a 35mph zone. thankfully her family was able to walk away without a scratch. Due to Metlife insurance being the most abhorrent car insurance companies I have ever heard of she had to buy her own new vehicle out of pocket. long story short after a while of looking she bought a very clean 1997 XLT expedition with the 5.4l. the only problem was two horribly leaking exhaust manifolds. $1,000 and 2 new manifolds and a EGR tube later she has the expedition running and sounding like it should. however, yesterday after picking up her truck from the exhaust shop the CEL came on. I checked codes and its coming up with p1131 and p1151 which according to my coworkers very expensive mactools code reader its a lean condition on both banks.. so seeing as how this only started AFTER the exhaust was fixed I am wondering what the problem could be. I had my sisters husband go under the truck and verify the o2 sensors are all plugged in and undamaged so Im wondering if anyone has any ideas what could cause this code to appear directly after exhaust repairs were made? thanks for the help!

 

[jlo82585]

a little bit more info on this issue, it seems to set exclusively on the second drive cycle after being cleared, I reset the ECM and it made no difference. I printed off ford diagnostics for this code and it says nothing about it being a faulty O2 sensor and to check fuel and induction systems so that may be where I start. Just wondering if anyone has ever seen this set of codes before.

 

[Bowesmobile]

Here's some light reading on one of those codes.

http://www.expeditionforum.com/f42/2000-eddie-bauer-25840/

Here's some more...

http://www.expeditionforum.com/f42/97-expy-p1131-after-fuel-pump-replacement-23656/

 

[jlo82585]

thanks, I saw in one of them it was suggested to check the hoses to the DPFE sensor, if those get installed backwards will it trip a code? both tube are next to each other on the manifold so does it make a difference which tube is installed into the nipple on the DPFE sensor?