P0171/p0174
Thread Starter
|
New User
Joined: Aug 2006
Posts: 4
Likes: 0
P0171/p0174
My wife was driving her 2001 Ford Explorer XLT when the "check engine" light came on. My wife said she drove to the mailbox and her car stalled and she had to restart the car. I decided to drive the car to the local Autozone for a "free check engine" diagnosis and the codes P0171/P0174 came across the scan tool. When the guy went to the book to look up the problem, he showed me four possible problems. 1) MAF 2) bad oxygen sensors 3) misfire ignition 4) clogged fuel injectors. I have been driving the car for a few hours now. Seems to be okay. Maybe idle a little high than normal. What could really be the problem?
….
Senior User
Joined: Oct 2004
Posts: 418
Likes: 0
From: Richmond, TX
P0171 System Too Lean (Bank 1)
P0174 System Too Lean (Bank 2)
Check for a vacuum leak first, somewhere around the intake area. Its not O2 sensors, they do not fail that fast nor will they both fail at the same time like this. Other things you can look at are a dirty MAF or the fuel filter needs to be replaced.
Basically you are either getting too much air, or not enough fuel.
P0174 System Too Lean (Bank 2)
Check for a vacuum leak first, somewhere around the intake area. Its not O2 sensors, they do not fail that fast nor will they both fail at the same time like this. Other things you can look at are a dirty MAF or the fuel filter needs to be replaced.
Basically you are either getting too much air, or not enough fuel.
Last edited by 01silvergt; Aug 29, 2006 at 07:31 AM.
Senior User
Joined: Aug 2005
Posts: 182
Likes: 0
I'm with Steve.
Autozone are great for the free checks but their diagnosis sucks. NOTHING in p0171/p0174 states that there are ANY bad components.
Becuase you have both banks running lean you should check it out ASAP. Lean running conditions can cause the engine to run much hotter than usual which can lead to cylinder head and/or valve damage due to scorching from the extreme gas temperatures.
Definitely check for a vacuum leak (search for my username, I've described it over and again so now I just send people to my previous posts) and also be prepared to swap the intake manifild gaskets (again, I've described how before. check it out).
That'll fix your lean condition.
Autozone are great for the free checks but their diagnosis sucks. NOTHING in p0171/p0174 states that there are ANY bad components.
Becuase you have both banks running lean you should check it out ASAP. Lean running conditions can cause the engine to run much hotter than usual which can lead to cylinder head and/or valve damage due to scorching from the extreme gas temperatures.
Definitely check for a vacuum leak (search for my username, I've described it over and again so now I just send people to my previous posts) and also be prepared to swap the intake manifild gaskets (again, I've described how before. check it out).
That'll fix your lean condition.
Senior User
Joined: Feb 2003
Posts: 147
Likes: 0
From: Ardmore
You might also check your fuel filter and fuel pump. I had these codes and tried for months to diagnose them. I followed the ford diagnosis tree and found everything to check ok. I found my problem when the fuel pump failed on me while on vacation. I changed the fuel pump in an Auto Zone parking lot at 9 o'clock at night ( of course the tank was full of fuel). The codes have not returned since, and that was almost a year ago.
New User
Joined: Sep 2006
Posts: 1
Likes: 0
01 Sport Trac
I have the same truck. My truck began acting the same way. The idle issue was resolved by replacing the cold air idle valve. It is located under the platic cover on the intake manifold. It is only 6 small bolts and about 15 minutes to replace.
I believe the cost was around 75.00 for the part. I also stoped using any fuel with ethonal. BTW I had to rebuild transmission at 55,000 miles. I don't know is this a common problem or just a condition caused by the x-wife.
Good Luck!
I believe the cost was around 75.00 for the part. I also stoped using any fuel with ethonal. BTW I had to rebuild transmission at 55,000 miles. I don't know is this a common problem or just a condition caused by the x-wife.
Good Luck!
Thread
Thread Starter
Forum
Replies
Last Post
nddragon01
2004 - 2008 F150
2
Feb 7, 2017 07:18 PM
