Rough Idle? CEL?, P0171,P0174 - Some simple things to check first

[wakeboarderNH]

It is normal, over the years the rubber elbow weakens and the vacuum effect ends up collapsing it. Mine was collapsed when I replaced mine, and it crumbled in my hands as I took it out.

That makes sense. Mine looks a little rough. I cleaned my MAF and my throttle body/intake just because too. My throttle body was dirty as sin so I could only imagine how the MAF was. Seems to be better now though, My elbow comes in tomorrow from Ford. Then I just gotta fix my heater hose.

Good day tomorrow for sure!

 

[nightsun1]

Just wanted to say thanks for posting this. I did some searching around and got lucky to have come across this thread. I was having these same issues during the cold months over the last year. Over the last week (as temps dropped into the 40's here in South, TX) the idle quality deteriorated to the point that I was unwilling to drive my 2000 Expy. First thing I did was look for vacuum leaks. I found a few. The worst was at the elbow connected to the pcv valve. It had completely caved in on itself and actually had a tear at the bend. I went to Oriely's and purchased the el below for 8 bucks and a new pcv valve for 3 bucks. I also changed out the hose connected at the upper rear port off the throttle body housing as it was severly corroded. I also cleaned the maf just to be on the safe side. Took it for a drive and it drove great and most importantly idles great. Here are some pics of the el I purchased. Thanks again.

 

[jv2000]

Dude, this post is awesome thanks for the info. I did a general write up on these codes if it will help anyone:

P0171 and P0174 OBDII Code Diagnosis

I still have not tracked down the cause in my Expedition but i'll report back when I do...

 

[Cedge1]

Thanks for this thread. The CEL was persistent in spite of my best efforts. 3 minutes after reading this thread, the problem was located and a temp fix made. Got the elbow for 10 bucks, today, at local parts house and the 03 EB is back to running smooth as silk. Awesome write up.

Steve