• Welcome Visitor! Please take a few seconds and Register for our forum. Even if you don't want to post, you can still 'Like' and react to posts.

2.3L ('02-'11) P0171 fuel trims




Dirtman

Former Middleweight Moss Fighting Champion
Joined
May 28, 2018
Messages
19,304
Reaction score
13,326
Points
113
Location
41N 75W
Vehicle Year
2009
Engine Type
2.3 (4 Cylinder)
Transmission
Automatic
2WD / 4WD
2WD
Total Lift
It's up there.
Total Drop
It's down there.
Tire Size
Round.
My credo
I poop in the furnace.
The only reason the downstream (B1S2) sensor would fluctuate that much would be if the cat has failed but you would get a CEL. Are hou sure you're not looking at the UPSTREAM (B1S1) o2 sensor data?
 

tatermatt90

Member
Joined
Aug 6, 2020
Messages
34
Reaction score
1
Points
8
Location
ga
Yes b1s2 voltage at idle ranges from 0 to .7 v. Under acceleration it shows .8 v but will drop low. The b1s2 percentage is steady at 99.2
 

Orca

Active Member
Joined
Jul 30, 2020
Messages
141
Reaction score
37
Points
28
Location
USA
Vehicle Year
2004
Make / Model
Ford Ranger
Engine Type
4.0 V6
Transmission
Automatic
2WD / 4WD
4WD
The b1s2 percentage is steady at 99.2
A few quick thoughts that may help a bit...

Your Zurich ZR13 scantool can graph up to 2 PIDs simultaneously. It would be very helpful if you could post a screenshot of your scantool while graphing the "O2S B1S1" and "O2S B1S2" voltages, either individually or (preferably) together.

Be aware that the steady 99.2% you're seeing for PID "STFT B1S2" means that that particular STFT value is meaningless -- 99.2% is how it says that that sensor is "not used in the calculation", which makes sense because "STFT BxS2" would be the PID associated with a downstream sensor.

In general, be reasonably careful with your interpretation and reporting of these PIDs. It can get quite confusing because the OBD2 standard (and, hence, your scantool) PIDs include STFT for a given bank in 3 places -- STFT for the bank, STFT for the upstream sensor on the bank (which always seems to match the former value, in my experience), and STFT for the downstream sensor on the bank (which is the meaningless PID I refer to above). Personally, I would focus only on the 1st value for STFT (i.e. what your scantool reports as "STFT B1", per the 1st image in your 1st post).

EDIT: Removed references to "Bank 2". I forgot that we're talking about a 2.3L engine here, which has only 1 bank, as your latest screenshot with the "O2SLoc" PID made clear!
 
Last edited:

tatermatt90

Member
Joined
Aug 6, 2020
Messages
34
Reaction score
1
Points
8
Location
ga
So are the high fuel trims under load caused by dirty injectors? Truck sat for a year
 

Sponsored Ad


Sponsored Ad

Members online

Member & Vendor Upgrades

For a small yearly donation, you can support this forum and receive a 'Supporting Member' banner, or become a 'Supporting Vendor' and promote your products here. Click the banner to find out how.

Truck of The Month


Kirby N.
March Truck of The Month

Recently Featured

Want to see your truck here? Share your photos and details in the forum.

Follow TRS On Instagram

TRS Events

25th Anniversary Sponsors

Check Out The TRS Store


Sponsored Ad


Sponsored Ad

Sponsored Ad


Amazon Deals

Top