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P0171 Diagnostic Trouble Code Discussion for August 2005

Fuel System Lean (Bank 1)


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Trouble Ticket Help Requests for DTC P0171
Help Request Posted
1997 Chevrolet Express 3500 5.7L Excessive Emissions, Poor Idle Quality, Misfire, MIL Lamp on VIN: 1G45DC2R0V
P0171: Fuel Trim System Lean (Bank 1). Posting this one for a friend. This vehicle came in with both banks lean codes and o2 codes. Tuneup was done elsewhere. All tuneup items were checked and double checked. Spider injection unit from the injector guru was installed. Same problem. Idle miss and wo...
August 02, 2005
1996 Ford E-350 Econoline 7.5L MIL Lamp on, Loss of Power VIN: 1FDKE30G8T
P0171: Bank 1 Lean AF Ratio. Proformance seems to drop off about 50mph like it is running out of fuel. I am not seeing fuel trim readings in the positive area but at idle acturally minus figures of(- 7-12 %) il light is on with codes above. 30psi seems like low limit.Is there an output te...
August 03, 2005
1996 Jeep Grand Cherokee Laredo 4.0L Surge VIN: 1J4GZ58S9T
P0171: Fuel System Lean (Bank 1). ... could find wrong was the 2 code in history P0171 Lean Exhaust & P0172 Rich exhaust. Found O2 sensor started cold with a voltage of 4.5 volts. Replaced both O2 sensors with no change in voltage or concern. Cleared codes,...
August 03, 2005
1995 Ford Windstar GL 3.8L MIL Lamp on VIN: 2FMDA514DS
P0171: lean exhaust bank 1. the vehicle fails state emission testing due to obdii testing for the codes previously stated. during testing i found that in scan data that the computer sees the baro reading to be 22.3 hg. in our area the baro reading flucuates normaly in the 29.1-29.9 range...
August 08, 2005
1999 Lexus ES300 3.0L MIL Lamp on VIN: JT8BF28G5X
P0171: Fuel System Too Lean (Bank 1). ... engine light on. Checked codes and found P0171 and P0420. I figured out that the maf sensor was giving a false reading. Replaced sensor. Customer wanted an injection service and fuel filter replaced also. Completed that ...
August 09, 2005
2003 Ford Taurus LX 3.0L Poor Idle Quality VIN: 1FAFP52V8W
P0171: System lean bank 1. ... that came in with P0171 and P0174 about 1000 miles ago (ran great). STFT was constantly of 25% and LTFT was at 28%. Diagnosed MAF and dirty injectors. Replaced MAF and R&R injectors for cleaning. After repair cleared codes and drove. Did some WOT drivi...
August 10, 2005
1999 Ford Windstar 3.8L Hesitation, Surge, Stall VIN: 2FMDA51UXW
Not sure if this pertains here or not. Ford has a TSB 03-16-1 for this condition. Reprogramming,replacement of the valve cover (LH), removal of the intake (upper), cleaning of the EGR ports,replacement of port gaskets and isolator bolts are what they call for ...
August 11, 2005
2001 Nissan Sentra GXE 1.8L Poor Idle Quality, Misfire, MIL Lamp on VIN: 3N1CB51D51
P0171: Fuel Trim Lean. ... codes po171 and po174. Idle is rough, it is worse when cold scan data shows it is compensating 110%+ both banks. checked fuel pressure 35+psi, check for vacuum leaks none found. Also is setting code p1320, could this be caused by lean misfire? Tried to cle...
August 11, 2005
1999 Ford E-250 Econoline 5.4L Excessive Emissions, No Start, Poor Idle Quality, Hesitation, Cuts out, Stall, MIL Lamp on VIN: 1FTNE24L6X
P0171: system lean B 1. Hi freinds I need help bad! This 5.4l will run just fine most of the time but on ocasion it severly laks power & has spark knock. one day of driving the van started running very poorly, blowing black smoke bad, wouldnt pull its self in gear, and some times...
August 14, 2005
1999 Honda Accord LX 2.3L Hesitation, Surge, MIL Lamp on VIN: JHMCG5641X
P0171: Fuel System Too Lean (Bank 1). Brought vehicle back and same code for bank 1 system lean. Long term fuel trim were about 12. O2 sensor was toggling like it should and downstream steady reading. Map reading about 8.5in of vacuum at idle and about 11 or so driving in town. Compared it to a sm...
August 15, 2005
1997 Ford F-150 4.6L Poor Idle Quality, Stall, MIL Lamp on VIN: 1A2B3C4D9G
P0171: system lean bank one. ... normally is an easy job has become a nightmare.vehicle came in with cel iluminated and p0171/p0174.also rough run at idle. every one will say clean maf and reset kam right.i did and all was well for about 15 min.short term trims go to +52.3 both banks and ...
August 18, 2005
1996 Chrysler Concorde LX 3.5L MIL Lamp on VIN: 2C3HD56F9T
P0171: Fuel System Lean (Bank 1). ... complaint that the check engine light was on and it was idling poorly and stalling. It had the Chrysler code 51-fuel system lean/at limit bank one and the obdII version of p0171 Bank One System too lean. It never really ran bad for us...
August 19, 2005
1998 Chevrolet Astro 4.3L Hesitation, Stall VIN: 1GNDM19W4W
P0171: Fuel Trim System Lean (Bank 1). Vehicle came in with no MIL,new fuel pump and filter and the same symptom as before he had fuel pump and filter replaced. Started out as an intermittent hesitation on acceleration. Fuel pump was making alot of rattling noise at idle. I condemned new fuel pump ...
August 20, 2005
2001 Chevrolet Prizm 1.8L MIL Lamp on VIN: 1Y1SK52871
P0171: Fuel System Too Lean. It seems like all of the wierd ones come up at the same time. This one has a lean code. The long-term fuel trim is staying at or above 30% at 65-70 mph. I first inspected the MAF and cleaned a bit of oily crud from it. No difference. I checked the fuel pressur...
August 22, 2005
1997 Ford Contour GL 2.0L Poor Idle Quality, Hesitation, Surge, Cuts out, Stall, MIL Lamp on VIN: 3FALP653XV
P0171: . Ok so now sence this is my Pastors car i now get it Gave them mine til i can get this ford fixed, i cleared code and it sets a MAF code pending po103 with in 5 minutes, the main problem is car start well but when idling if you give it gas really slow at about ...
August 24, 2005
2000 Toyota 4Runner Limited 3.4L Hesitation, Cuts out, Poor Fuel Economy, MIL Lamp on VIN: JT3HN87R1Y
P0171: Fuel System Too Lean (Bank 1). Customer has complaint of unstable idle (scan tool shows it trying to remove 18% from LT fuel trim) and lack of power going down road scan tool shows it trying to add 35% to LT fuel trim). Checked basics MAF(OK) O2 (OK) Coolant temp (OK) when we checked fuel p...
August 24, 2005
2002 Land Rover Freelander SE 2.5L check engine light VIN: SALNY22222
P0171: Left front O2 lean. Thanks in advance for any help.This vehicle came in with the check engine light on and the customer stating that the only problem they had was that the vehicle smelled hot when they shut it off.I cleared the codes and road tested the vehicle for over 30 miles ...
August 25, 2005
1997 Ford F-150 4.6L Poor Idle Quality, Stall, MIL Lamp on VIN: 1A2B3C4D9G
P0171: system lean bank one. ... normally is an easy job has become a nightmare.vehicle came in with cel iluminated and p0171/p0174.also rough run at idle. every one will say clean maf and reset kam right.i did and all was well for about 15 min.short term trims go to +52.3 both banks and ...
August 26, 2005
1997 Chevrolet Express 3500 5.7L Excessive Emissions, Poor Idle Quality, Misfire, MIL Lamp on VIN: 1G45DC2R0V
P0171: Fuel Trim System Lean (Bank 1). Posting this one for a friend. This vehicle came in with both banks lean codes and o2 codes. Tuneup was done elsewhere. All tuneup items were checked and double checked. Spider injection unit from the injector guru was installed. Same problem. Idle miss and wo...
August 02, 2005
1996 Ford E-350 Econoline 7.5L MIL Lamp on, Loss of Power VIN: 1FDKE30G8T
P0171: Bank 1 Lean AF Ratio. Proformance seems to drop off about 50mph like it is running out of fuel. I am not seeing fuel trim readings in the positive area but at idle acturally minus figures of(- 7-12 %) il light is on with codes above. 30psi seems like low limit.Is there an output te...
August 03, 2005
1996 Jeep Grand Cherokee Laredo 4.0L Surge VIN: 1J4GZ58S9T
P0171: Fuel System Lean (Bank 1). ... could find wrong was the 2 code in history P0171 Lean Exhaust & P0172 Rich exhaust. Found O2 sensor started cold with a voltage of 4.5 volts. Replaced both O2 sensors with no change in voltage or concern. Cleared codes,...
August 03, 2005
1995 Ford Windstar GL 3.8L MIL Lamp on VIN: 2FMDA514DS
P0171: lean exhaust bank 1. the vehicle fails state emission testing due to obdii testing for the codes previously stated. during testing i found that in scan data that the computer sees the baro reading to be 22.3 hg. in our area the baro reading flucuates normaly in the 29.1-29.9 range...
August 08, 2005
1999 Lexus ES300 3.0L MIL Lamp on VIN: JT8BF28G5X
P0171: Fuel System Too Lean (Bank 1). ... engine light on. Checked codes and found P0171 and P0420. I figured out that the maf sensor was giving a false reading. Replaced sensor. Customer wanted an injection service and fuel filter replaced also. Completed that ...
August 09, 2005
2003 Ford Taurus LX 3.0L Poor Idle Quality VIN: 1FAFP52V8W
P0171: System lean bank 1. ... that came in with P0171 and P0174 about 1000 miles ago (ran great). STFT was constantly of 25% and LTFT was at 28%. Diagnosed MAF and dirty injectors. Replaced MAF and R&R injectors for cleaning. After repair cleared codes and drove. Did some WOT drivi...
August 10, 2005
1999 Ford Windstar 3.8L Hesitation, Surge, Stall VIN: 2FMDA51UXW
Not sure if this pertains here or not. Ford has a TSB 03-16-1 for this condition. Reprogramming,replacement of the valve cover (LH), removal of the intake (upper), cleaning of the EGR ports,replacement of port gaskets and isolator bolts are what they call for ...
August 11, 2005
2001 Nissan Sentra GXE 1.8L Poor Idle Quality, Misfire, MIL Lamp on VIN: 3N1CB51D51
P0171: Fuel Trim Lean. ... codes po171 and po174. Idle is rough, it is worse when cold scan data shows it is compensating 110%+ both banks. checked fuel pressure 35+psi, check for vacuum leaks none found. Also is setting code p1320, could this be caused by lean misfire? Tried to cle...
August 11, 2005
1999 Ford E-250 Econoline 5.4L Excessive Emissions, No Start, Poor Idle Quality, Hesitation, Cuts out, Stall, MIL Lamp on VIN: 1FTNE24L6X
P0171: system lean B 1. Hi freinds I need help bad! This 5.4l will run just fine most of the time but on ocasion it severly laks power & has spark knock. one day of driving the van started running very poorly, blowing black smoke bad, wouldnt pull its self in gear, and some times...
August 14, 2005
1999 Honda Accord LX 2.3L Hesitation, Surge, MIL Lamp on VIN: JHMCG5641X
P0171: Fuel System Too Lean (Bank 1). Brought vehicle back and same code for bank 1 system lean. Long term fuel trim were about 12. O2 sensor was toggling like it should and downstream steady reading. Map reading about 8.5in of vacuum at idle and about 11 or so driving in town. Compared it to a sm...
August 15, 2005
1997 Ford F-150 4.6L Poor Idle Quality, Stall, MIL Lamp on VIN: 1A2B3C4D9G
P0171: system lean bank one. ... normally is an easy job has become a nightmare.vehicle came in with cel iluminated and p0171/p0174.also rough run at idle. every one will say clean maf and reset kam right.i did and all was well for about 15 min.short term trims go to +52.3 both banks and ...
August 18, 2005
1996 Chrysler Concorde LX 3.5L MIL Lamp on VIN: 2C3HD56F9T
P0171: Fuel System Lean (Bank 1). ... complaint that the check engine light was on and it was idling poorly and stalling. It had the Chrysler code 51-fuel system lean/at limit bank one and the obdII version of p0171 Bank One System too lean. It never really ran bad for us...
August 19, 2005
1998 Chevrolet Astro 4.3L Hesitation, Stall VIN: 1GNDM19W4W
P0171: Fuel Trim System Lean (Bank 1). Vehicle came in with no MIL,new fuel pump and filter and the same symptom as before he had fuel pump and filter replaced. Started out as an intermittent hesitation on acceleration. Fuel pump was making alot of rattling noise at idle. I condemned new fuel pump ...
August 20, 2005
2001 Chevrolet Prizm 1.8L MIL Lamp on VIN: 1Y1SK52871
P0171: Fuel System Too Lean. It seems like all of the wierd ones come up at the same time. This one has a lean code. The long-term fuel trim is staying at or above 30% at 65-70 mph. I first inspected the MAF and cleaned a bit of oily crud from it. No difference. I checked the fuel pressur...
August 22, 2005
1997 Ford Contour GL 2.0L Poor Idle Quality, Hesitation, Surge, Cuts out, Stall, MIL Lamp on VIN: 3FALP653XV
P0171: . Ok so now sence this is my Pastors car i now get it Gave them mine til i can get this ford fixed, i cleared code and it sets a MAF code pending po103 with in 5 minutes, the main problem is car start well but when idling if you give it gas really slow at about ...
August 24, 2005
2000 Toyota 4Runner Limited 3.4L Hesitation, Cuts out, Poor Fuel Economy, MIL Lamp on VIN: JT3HN87R1Y
P0171: Fuel System Too Lean (Bank 1). Customer has complaint of unstable idle (scan tool shows it trying to remove 18% from LT fuel trim) and lack of power going down road scan tool shows it trying to add 35% to LT fuel trim). Checked basics MAF(OK) O2 (OK) Coolant temp (OK) when we checked fuel p...
August 24, 2005
2002 Land Rover Freelander SE 2.5L check engine light VIN: SALNY22222
P0171: Left front O2 lean. Thanks in advance for any help.This vehicle came in with the check engine light on and the customer stating that the only problem they had was that the vehicle smelled hot when they shut it off.I cleared the codes and road tested the vehicle for over 30 miles ...
August 25, 2005
1997 Ford F-150 4.6L Poor Idle Quality, Stall, MIL Lamp on VIN: 1A2B3C4D9G
P0171: system lean bank one. ... normally is an easy job has become a nightmare.vehicle came in with cel iluminated and p0171/p0174.also rough run at idle. every one will say clean maf and reset kam right.i did and all was well for about 15 min.short term trims go to +52.3 both banks and ...
August 26, 2005