My check engine light came on this Morning P0171 code?

Tiny
MRDIXON
  • MEMBER
  • 2006 FORD RANGER
  • 2.3L
  • 4 CYL
  • 2WD
  • MANUAL
  • 113,900 MILES
My check engine light came on this morning as soon as I cranked it up. I took it to Advance Auto and they read the OBD code and it's P0171. Something about bank 1 running lean. That's all they would tell me. Is it safe to drive the truck until I find out what this is?
Sunday, November 2nd, 2014 AT 2:32 PM

12 Replies

Tiny
SATURNTECH9
  • MECHANIC
  • 30,869 POSTS
Yes it should be safe to drive I would be looking for a vacuum leak and checking the actual fuel pressure. this guide can help up fix it.

https://www.2carpros.com/articles/repair-lean-mixture-codes-p0171-or-p0174-on-some-manufacturers

Please run down this guide and report back.
Was this
answer
helpful?
Yes
No
+1
Saturday, April 25th, 2020 AT 2:30 PM
Tiny
MRDIXON
  • MEMBER
  • 13 POSTS
I found the vacuum leak. It's on what looks like a preformed hose at the back of the engine near the main vacuum line. I can't tell where this hose goes and I don't know the name of it to buy a new one. I've been trying to fine pictures of it and the best thing I can come up with is the EGR tube? There are two of these hose fittings one on top of the other but I can't figure out where it's going. Any suggestions? Thanks!
Was this
answer
helpful?
Yes
No
Saturday, April 25th, 2020 AT 2:30 PM
Tiny
MRDIXON
  • MEMBER
  • 13 POSTS
I found it, it was the PCV line all fixed once I cleared the codes.
Was this
answer
helpful?
Yes
No
Saturday, April 25th, 2020 AT 2:30 PM
Tiny
MLT1956
  • MEMBER
  • 1 POST
  • 2000 FORD RANGER
My check engine light came on so my husband asked me to take it to a nearby parts store and I used their computer to find out why it was on. It said oxygen sensor bank 1 system too lean. So my husband changed the front oxygen sensor. I then drove ot for a couple of days and the light came back on. We have had it to several garages and they all say they don't know. It still says system too lean bank 1 with the code of P0171. I don't want to keep driving it with this problem but I don;t have much choice. I drive 64 miles a day in a rural area and I need this pickup running right. Please help!
Was this
answer
helpful?
Yes
No
Wednesday, June 9th, 2021 AT 4:41 PM (Merged)
Tiny
TOBYBENSON
  • MEMBER
  • 1 POST
I find it common on almost all older vehicles that an exhaust leak on the bank side can cause this issue.
Was this
answer
helpful?
Yes
No
Wednesday, June 9th, 2021 AT 4:41 PM (Merged)
Tiny
WHEELCHAIRDUDE49
  • MEMBER
  • 73 POSTS
  • 2000 FORD RANGER
  • 4 CYL
  • 2WD
  • AUTOMATIC
  • 60,000 MILES
P0171 code came back after a week when I changed vacuum hose and changed MAF sensor. Have checked for
Vac leaks cant find one. I did buy a new code reader ( equus Innova 3140 do have the freeze frame and live data recorded Hope this will get me closer to solving the problem.
Dtc for which Freeze frame was stored. P0171
fuel system 1 status Closed loop
fuel system 2 status not supported
Calculated load value 36.86%
coolant temp 82 c
short term fuel trim 7.03 %
long term fuel trim 25.00%
engine rpm 1846 rpm
vehicle speed 46 mph

New to this Obd II so really don't know what this all means. Can you help out?
Was this
answer
helpful?
Yes
No
Wednesday, June 9th, 2021 AT 4:44 PM (Merged)
Tiny
OBXAUTOMEDIC
  • MECHANIC
  • 3,711 POSTS
Hello,

A P0171 lean code for bank 1 is the cylinder bank on the RIGHT (passenger) side of the engine on Ford vehicles with a V6 or V8 engine. This guide will help

https://www.2carpros.com/articles/repair-lean-mixture-codes-p0171-or-p0174-on-some-manufacturers

A lean fuel condition may exist if the engine is sucking in too much air and/or the fuel system is not delivering enough fuel. If bad enough, a lean fuel condition may cause lean misfire, a rough idle, hesitation or stumble when accelerating, and/or poor engine performance.

Unmetered air can enter the engine through a vacuum leak, a dirty airflow sensor that is not reading airflow accurately, an EGR valve is not closing and is leaking exhaust into the intake manifold, an EGR valve that is allowing too much flow (because the EGR differential pressure sensor that monitors EGR flow is faulty and is under-reporting EGR flow).

If the problem is not enough fuel, the underling cause may be a weak fuel pump, restricted fuel filter, leaky fuel pressure regulator or dirty fuel injectors. Will need to check fuel pressure...

Ford p0171 AND p0174 lean codes can also be set by a bad EGR differential pressure sensor. These sensors have a very high failure rate once a vehicle has more than about 60,000 miles on the odometer or is more than five or six years old.

The DPFE sensor is mounted on the engine, and is attached with two rubber hoses to the tube that routes exhaust gas to the EGR valve. The original equipment sensor has an rectangular aluminum housing about three inches long.
Was this
answer
helpful?
Yes
No
-1
Wednesday, June 9th, 2021 AT 4:44 PM (Merged)
Tiny
WHEELCHAIRDUDE49
  • MEMBER
  • 73 POSTS
New hose on valve cover to throttle body. Was one of 2 hoses I changed. Heater control works fine.
Was this
answer
helpful?
Yes
No
+1
Wednesday, June 9th, 2021 AT 4:44 PM (Merged)
Tiny
WHEELCHAIRDUDE49
  • MEMBER
  • 73 POSTS
Not yet. Just put another new MAF sensor on it yesterday and a new pcv and hose changed the fuel filter too. That fixed it.
Was this
answer
helpful?
Yes
No
Wednesday, June 9th, 2021 AT 4:44 PM (Merged)
Tiny
2BOSS'S
  • MEMBER
  • 3 POSTS
  • 1999 FORD RANGER
  • 6 CYL
  • 4WD
  • AUTOMATIC
  • 11,200 MILES
I have 2 trouble codes that keep coming up on my truck, they are p0171 and p0174. Tells me that it is too lean on bank 1 and 2. How can I fix this? I have been told that it is the oxygen sensors, but how many are there on my truck? Or is it some thing else?I would appreciate any help that anyone has to offer. Thanks
Was this
answer
helpful?
Yes
No
Wednesday, June 9th, 2021 AT 4:46 PM (Merged)
Tiny
ZUE
  • MEMBER
  • 76 POSTS
Check for a vacuum leak(s) around the intake area. This is a typical cause of the codes you are seeing. Poor man's vacuum leak test is to spray starter fluid around the intake components while engine is at idle. If you hear a slight increase in the engine RPMs for just a second then you have located the leak area. Starter fluid gets sucked into the intake area which causes the increase in RPMs. This guide can help

https://www.2carpros.com/articles/how-to-use-an-engine-vacuum-gauge
Was this
answer
helpful?
Yes
No
Wednesday, June 9th, 2021 AT 4:46 PM (Merged)
Tiny
2BOSS'S
  • MEMBER
  • 3 POSTS
Thanks for all your help I got it fixed. Had a vacuum leak.
Was this
answer
helpful?
Yes
No
-1
Wednesday, June 9th, 2021 AT 4:46 PM (Merged)

Please login or register to post a reply.

Sponsored links