Too lean bank 1
Thread Starter
|
Senior User
Joined: Dec 2003
Posts: 404
Likes: 0
From: Groton, CT
Too lean bank 1
BigRed started throwing the old 171 code. I have seen the 171/174 codes when my MAF sensor was acting up, but not the 171 alone. I am running at PRO M aftermarket MAF, so I disconnected the battery and re-installed my OEM MAF. The 171 code (mixture too lean bank 1) throws again. Took my trusty Superchips 1715 and restored the stock program (just eliminating things one at a time) and 171 code comes back. I have indications that she is running rich (exhaust will bring tears to your eyes) so I figure the PCM thinks she is lean and is dumping fuel to compensate.
I am guessing the O2 sensor at this point, any of you remember which side is Bank 1 (getting old...memory shot...afraid to think about what goes next)? Also, any other possibilities that I am overlooking?
I am guessing the O2 sensor at this point, any of you remember which side is Bank 1 (getting old...memory shot...afraid to think about what goes next)? Also, any other possibilities that I am overlooking?
Lead Driver
Joined: Sep 2002
Posts: 9,182
Likes: 12
From: Gateway to the West
Not 100% certain but it would seem to make sense that bank one would be the sensor on the driver's side since those are the first four cylinders, hence bank one of of two... the second bank being cylinders 5-8.
Thread Starter
|
Senior User
Joined: Dec 2003
Posts: 404
Likes: 0
From: Groton, CT
Grey, had me questioning my sanity there for a second. Went and checked my manuals to see if I had been screwed up all these years. I agree with your logic that bank 1 is probably for cylinders 1-4, but 1-4 is on the passenger side not the driver's side.
Now heaven forbid that Chilton's and Haynes could ever make a mistake
so if I am all screwed up please set me straight. Both manuals show 1-4 on passenger side with cylinder 1 right behind the alternator. If I remember correctly my underhood diagram shows the same thing.
Can't go check right now, Mother Nature having a good old time up here in Connecticut right now. Looking at the four foot snow drift where my front sidewalk used to be, I just can't wait to get to my snow shovel. Think maybe I'll call the Emergency Room first and make a reservation.
Now heaven forbid that Chilton's and Haynes could ever make a mistake
so if I am all screwed up please set me straight. Both manuals show 1-4 on passenger side with cylinder 1 right behind the alternator. If I remember correctly my underhood diagram shows the same thing.
Can't go check right now, Mother Nature having a good old time up here in Connecticut right now. Looking at the four foot snow drift where my front sidewalk used to be, I just can't wait to get to my snow shovel. Think maybe I'll call the Emergency Room first and make a reservation.
Thread Starter
|
Senior User
Joined: Dec 2003
Posts: 404
Likes: 0
From: Groton, CT
Trending Topics
Tuned
Joined: Mar 2001
Posts: 383
Likes: 6
From: California
Doesn't the egr tube dump back into the 5-8 side? I've had problems with that bank of valves for years now. I don't know if I'm still following the problem here but maybe that will rattle someones thought process and help. Good luck
Mike
Mike
FTE Stories
Ford Trucks for Ford Truck Enthusiasts
Top 10 Most Expensive Ford Trucks Ever Sold on Bring a Trailer
Joe Kucinski
2027 Ford Super Duty Buyer's Guide (Every Model, Engine, & Package)
Brett Foote
Top 10 Ford Truck Tragedies
Joe Kucinski
AEV FXL Super Duty - the Super Duty Raptor Ford Doesn't Make
Brett Foote
Lobo Vs Lobo: Proof the F-150 Lobo Should Be Even Lower!
Michael S. Palmer
Ford's 2001 Explorer Sportsman Concept Looks For a New Home
Verdad Gallardo
10 Best Ford Truck Engines We Miss the Most!
Joe Kucinski
2026 Shelby F-150 Off-Road: Better Than a Raptor R?
Brett Foote
2027 Super Duty Carhartt Package First Look: 12 Things You NEED to Know!
Michael S. Palmer
Thread Starter
|
Senior User
Joined: Dec 2003
Posts: 404
Likes: 0
From: Groton, CT
OK fellow Bronconians, replaced the O2 sensor on the 1-4 side (bank 1?). Still getting OBD code 171 (System too lean Bank 1). Either we are off the mark on which side is Bank 1, or I am looking for something else. Visual inspection of wires was OK, no exhaust leaks, vacuum leaks or any other signs of foul play. No driveability issues whatsoever, although BigRed seems to be running happier with the new O2 sensor (could be my imagination...or perhaps the Bronc feels better having felt wrenches applied)
Any other thoughts?
Any other thoughts?
Thread Starter
|
Senior User
Joined: Dec 2003
Posts: 404
Likes: 0
From: Groton, CT
No. I know that you must power down computer when you replace the MAF Sensor, but I have never run across that recommendation for an O2 Sensor. What the heck, I'll give it a try. Thanks KB.
Thread Starter
|
Senior User
Joined: Dec 2003
Posts: 404
Likes: 0
From: Groton, CT
Plugs only a few months old. Nice and warm a relative term in Connecticut right now. Anything above 20 degrees is a heat wave. Disconnected battery for about 40 minutes this morning, now we wait and see.