Notices
1997 - 2003 F150 1997-2003 F150, 1997-1999 F250LD, 7700 & 2004 F150 Heritage
Sponsored by:
Sponsored by: Auxito

P0171 P0174 OBD 2 codes???

Thread Tools
 
Search this Thread
 
Old Mar 3, 2004 | 11:49 AM
  #1  
ritchie46's Avatar
ritchie46
Thread Starter
|
Junior User
Joined: Mar 2004
Posts: 51
Likes: 0
P0171 P0174 OBD 2 codes???

I have a 1999 f150 4X4 with the 5.4, service engine light goes on with code p0174 and p0171. These codes go on after a couple of drives after resetting them. I looked these codes up and it says bank 1 and bank 2 system lean. Any Ideas? I have checked for a vacuume leak and can not find any. Thanks in advance
 
Reply
Old Mar 3, 2004 | 12:19 PM
  #2  
LxMan1's Avatar
LxMan1
Moderator
Joined: Dec 2001
Posts: 22,436
Likes: 17
From: Louisville,Ky.
Check the PCV hose assembly for cracking back behind the throttlebody elbow.
Also, clean the MAF (Mass-airflow sensor).

Jimmy
 
Reply
Old Mar 3, 2004 | 01:13 PM
  #3  
ritchie46's Avatar
ritchie46
Thread Starter
|
Junior User
Joined: Mar 2004
Posts: 51
Likes: 0
Thanks LxMan1, I did look at the PCV valve, has good suction and no cracks. I cleaned the MAF with a q-tip and alcohol and cleared the codes again. I also noticed the dip stick was not on all the way and If I remember this could cause the light to come on with this code. The truck still runs rough at idle, will wait and see if light comes on again.... (I have had this truck for about a month now and have changed the plugs and two COP's already for misfire codes, It has 90,000 miles on it) The truck has never ran smooth... Thanks for your input.
 
Reply
Old Mar 3, 2004 | 10:19 PM
  #4  
ritchie46's Avatar
ritchie46
Thread Starter
|
Junior User
Joined: Mar 2004
Posts: 51
Likes: 0
Went ahead and changed the PCV valve and the truck is running smoother...... will wait to see if light comes back on..... thanks again!
 
Reply
Old Mar 3, 2004 | 10:59 PM
  #5  
jns's Avatar
jns
Freshman User
Joined: Oct 2003
Posts: 25
Likes: 0
Another vote for cleaning the MAF sensor.I have a 98 4.6 and had a check engine light.I sprayed the MAF wires with electric-parts cleaner.I cleared the codes and haven't seen the check engine light back on since.Good luck.
 
Reply
Old Mar 4, 2004 | 12:23 AM
  #6  
LxMan1's Avatar
LxMan1
Moderator
Joined: Dec 2001
Posts: 22,436
Likes: 17
From: Louisville,Ky.
Good luck, My 5.4 has never been completely smooth. It is the nature of the beast they say.
Jimmy
 
Reply
Old Mar 7, 2004 | 05:58 PM
  #7  
ritchie46's Avatar
ritchie46
Thread Starter
|
Junior User
Joined: Mar 2004
Posts: 51
Likes: 0
Light went back on with same codes. I went ahead and changed the fuel filter drove it for the two trips required to set off the light and it went back on... p0171 and p0174, have changed the pcv and tubing as well as the fuelfilter, cleaned the mass airflow sensor and still getting this lean fuel code. This is the first ford I have had.... what a bummer.. any other thoughts out there?? thanks in advance
 
Reply
Old Mar 7, 2004 | 09:11 PM
  #8  
Ford Trucks 4 Life's Avatar
Ford Trucks 4 Life
New User
Joined: Feb 2004
Posts: 5
Likes: 0
I was wondering how do you pull the code and how do you reset it?
 
Reply
FTE Stories

Ford Trucks for Ford Truck Enthusiasts

story-0

10 Ways Ford is LOSING to the Competition

 Joe Kucinski
story-1

Top 6 Best Deals Available on New Fords & Lincolns Right Now

 Brett Foote
story-2

This Hennessey Takes the Expedition Tremor's Off-Roading Capability to the Next Level

 Verdad Gallardo
story-3

Top 10 Fords at 2026 Carlisle Ford Nationals

 Joe Kucinski
story-4

3 Best / 3 Worst Parts of Modern Ford Ownership

 Brett Foote
story-5

10 Amazing Upgrades That Solve Common Ford Truck Owner Headaches

 Pouria Savadkouei
story-6

Every 2026 Ford Engine Explained

 Brett Foote
story-7

10 Ugly Ford Trucks That We Still Kinda Love

 Joe Kucinski
story-8

10 Things Every Truck Owner NEEDS (2026 Edition)

 Michael S. Palmer
story-9

Rezvani's Latest Post-Apocalyptic Monster Is a Ford F-150 Raptor Underneath

 Verdad Gallardo
Old Mar 7, 2004 | 09:36 PM
  #9  
jns's Avatar
jns
Freshman User
Joined: Oct 2003
Posts: 25
Likes: 0
You can pull the codes by going to Auto Zone and borrowing a scan tool.It plugs right in to the diagnostic port on the lower right of the dash.After you get the codes,you can reset it.Ritchie46,a lean condition could possibly mean a faulty oxygen or MAF sensor if you've already tried cleaning the MAF and checked for vacuum leaks.Good luck and keep us posted.
 
Reply
Old Mar 7, 2004 | 10:11 PM
  #10  
Flash's Avatar
Flash
Posting Guru
Joined: Jul 2001
Posts: 1,914
Likes: 1
FWIW, I had the same code problem with my 02 4.6 SCrew. After doing the same as you have already and replacing the o2 sensors, I finally found a leak at the brake booster. If you get in the truck and occasionally the brakes are hard before startup- you have a bad booster. Cured my problem.
 
Reply
Old Mar 9, 2004 | 07:38 PM
  #11  
ritchie46's Avatar
ritchie46
Thread Starter
|
Junior User
Joined: Mar 2004
Posts: 51
Likes: 0
Thanks all, I went ahead and changed the maf, cleared the codes (I have my own reader) and the light has not came back on. I was told that sometimes when you put a new K&N filter or FIPK it can mess your sensor up. I guess if there is too much oil on the filter. Cleaning did not help this time. No more P0171 P0174 .... whooo hooo!
 
Reply
Old Mar 9, 2004 | 08:53 PM
  #12  
krunker's Avatar
krunker
Senior User
Joined: Feb 2004
Posts: 146
Likes: 0
From: LaGrande, OR
For future reference, never clean the MAF with a Q-tip, spary electrical parts cleaner or carb cleaner into it. Also, to check if its bad, unplug it and see if the problem gets worse, if it doesn't it's bad.
 
Reply
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
allvol
1997 - 2003 F150
4
Apr 2, 2016 01:39 PM
hhoelsc
1997 - 2006 Expedition & Navigator
152
Apr 1, 2016 09:26 AM
brian_06328
Explorer, Sport Trac, Mountaineer & Aviator
3
Oct 1, 2006 11:59 PM
njxlt
1997 - 2006 Expedition & Navigator
1
Sep 16, 2006 10:15 AM
BltFordTough
1983 - 2012 Ranger & B-Series
20
Nov 3, 2005 07:18 PM




All times are GMT -5. The time now is 12:28 PM.

story-0
10 Ways Ford is LOSING to the Competition

Slideshow: 10 ways Ford is losing to the competition

By Joe Kucinski | 2026-06-15 09:52:01


VIEW MORE
story-1
Top 6 Best Deals Available on New Fords & Lincolns Right Now

Some great targets in today's expensive world.

By Brett Foote | 2026-06-15 09:35:19


VIEW MORE
story-2
This Hennessey Takes the Expedition Tremor's Off-Roading Capability to the Next Level

Slideshow: The VelociRaptor Expedition gains a lift, upgraded suspension, Brembo brakes, and trail-ready equipment while retaining the stock 440-horsepower EcoBoost V6.

By Verdad Gallardo | 2026-06-12 11:01:55


VIEW MORE
story-3
Top 10 Fords at 2026 Carlisle Ford Nationals

Slideshow: Top 10 Fords at 2026 Ford Nationals

By Joe Kucinski | 2026-06-09 11:10:08


VIEW MORE
story-4
3 Best / 3 Worst Parts of Modern Ford Ownership

Based on years of owning multiple modern Ford products.

By Brett Foote | 2026-06-09 10:53:36


VIEW MORE
story-5
10 Amazing Upgrades That Solve Common Ford Truck Owner Headaches

SPONSORED: From muddy boots to rain-soaked cargo, these upgrades address some of the most common frustrations Ford truck owners face every day.

By Pouria Savadkouei | 2026-06-08 18:50:34


VIEW MORE
story-6
Every 2026 Ford Engine Explained

Here's everything you need to know about every Ford engine available for the 2026 model year.

By Brett Foote | 2026-06-05 12:58:01


VIEW MORE
story-7
10 Ugly Ford Trucks That We Still Kinda Love

Slideshow: 10 ugly Ford trucks that we still kinda love.

By Joe Kucinski | 2026-06-03 09:51:16


VIEW MORE
story-8
10 Things Every Truck Owner NEEDS (2026 Edition)

Slideshow: the best gifts for dads & grads

By Michael S. Palmer | 2026-06-03 15:43:58


VIEW MORE
story-9
Rezvani's Latest Post-Apocalyptic Monster Is a Ford F-150 Raptor Underneath

Slideshow: Called the Fortress, the 850-horsepower pickup combines Raptor underpinnings with military-inspired features, survival equipment, and a starting price of $285,000.

By Verdad Gallardo | 2026-06-03 11:38:36


VIEW MORE