|
Issues | Warranty | Recalls / TSB Problems, issues, recalls, TSBs |
|
Thread Tools | Search this Thread |
07-31-2019, 09:05 PM | #1 |
Senior Member
Join Date: Nov 2017
Drives: Black FRS
Location: California
Posts: 146
Thanks: 3
Thanked 27 Times in 19 Posts
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
|
Torque data log interpretation - Fuel Trim, AFR, Timing Etc
https://datazap.me/u/butterballz/log...6?log=0&data=5
Stock motor, stock intake, no tunes, stock exhaust system except for track pipe. Just want to make sure my readings are in the normal range. Some readings look off like AFR in the 20s etc. Thanks. |
07-31-2019, 09:25 PM | #2 |
Senior Member
Join Date: Jun 2014
Drives: WRB Subaru BRZ Limited 6MT
Location: United States
Posts: 141
Thanks: 17
Thanked 71 Times in 44 Posts
Mentioned: 3 Post(s)
Tagged: 1 Thread(s)
|
It isn't possible to determine if your actual AFRs are reasonable as you didn't track throttle position and/or engine load. With a stock engine and map, you will notice your AFR go to 20 anytime you come off throttle (engine braking). On full throttle with very high engine loading, you should see AFRs drop into the high 11s and low 12s. Cruising, constant throttle will result in AFRs around 14.5-14.83.
Your fuel trims look fine (no excursions above +10 summed or -10 summed). I wouldn't expect anything to change with just a catback exhaust. To be 100% sure, you will need to re-log with throttle position, engine load (if available on Torque - I can't remember), manifold vacuum, MAF voltage, engine RPM, and your short and long term trims. |
The Following User Says Thank You to theadmiral976 For This Useful Post: | Butterballz (07-31-2019) |
07-31-2019, 09:28 PM | #3 | |
Senior Member
Join Date: Nov 2017
Drives: Black FRS
Location: California
Posts: 146
Thanks: 3
Thanked 27 Times in 19 Posts
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
|
Quote:
|
|
07-31-2019, 09:35 PM | #4 |
Senior Member
Join Date: Jun 2014
Drives: WRB Subaru BRZ Limited 6MT
Location: United States
Posts: 141
Thanks: 17
Thanked 71 Times in 44 Posts
Mentioned: 3 Post(s)
Tagged: 1 Thread(s)
|
It's always interesting to log data like this. Recently, I had started to notice a slight dip in my fuel economy (~2 mpg highway, up to 5 mpg city). I logged data for a few days and uncovered slight changes in air flow that led me to a rather significant leak at my exhaust manifold (rusted gasket - I live in the Rust belt). Curiously, the exhaust leak noise I would have expected to hear wasn't very apparent in my situation, probably due to some combination of aftermarket header and catback exhaust. Anyway, replaced the gaskets and am getting the best fuel economy I've gotten in years (~32 mpg on 93 and 27 mpg E85 highway).
|
07-31-2019, 09:42 PM | #5 | |
Senior Member
Join Date: Nov 2017
Drives: Black FRS
Location: California
Posts: 146
Thanks: 3
Thanked 27 Times in 19 Posts
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
|
Quote:
|
|
07-31-2019, 09:53 PM | #6 | |
Senior Member
Join Date: Jun 2014
Drives: WRB Subaru BRZ Limited 6MT
Location: United States
Posts: 141
Thanks: 17
Thanked 71 Times in 44 Posts
Mentioned: 3 Post(s)
Tagged: 1 Thread(s)
|
Quote:
Just based on your log above, I would be confident in saying your trims look pretty darn good. Back when I ran a stock car, I would routinely notice total trims anywhere from -9 to +7, even when the car was only a few thousand miles old. Without the vacuum and load data, it is impossible to be 100% confident, but my bet is you don't have anything that would cause more than a slight (normal wear and tear-related) change in fuel economy. Another thing to think about is your O2 sensors. I doubt you have an issue with either the wideband or narrowband, but tracking their voltages could be really helpful as well just to be sure. The early narrowband sensors used in the manufacture of these cars were replaced with a new version, I think in 2015. If you have an older car, it's not impossible that the narrowband has gotten contaminated; although, it sounds like you haven't modified the primary cat so it's not too likely in your case. For me, within about 5,000 miles of switching to a catless header, I fouled the narrowband sensor which started messing with my trims (and thus fuel economy) in specific situations. |
|
07-31-2019, 11:02 PM | #7 | |
Senior Member
Join Date: Nov 2017
Drives: Black FRS
Location: California
Posts: 146
Thanks: 3
Thanked 27 Times in 19 Posts
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
|
Quote:
|
|
|
|
|
|
Similar Threads | ||||
Thread | Thread Starter | Forum | Replies | Last Post |
Anyone else with ECUTEK having fuel trim issues. | Shit Luck | Software Tuning | 12 | 11-14-2021 10:58 PM |
Delicious Tuning: Edelbrock E-Force Supercharger with Flex Fuel – Official Dyno Data | DeliciousTuning | Software Tuning | 53 | 10-19-2018 11:55 AM |
fuel trim | John27 | Scion FR-S / Toyota 86 GT86 General Forum | 2 | 04-21-2017 04:08 PM |
[OFT] Interest in Data Logs vs. GTA Fuel Grades | drewbot | CANADA | 5 | 11-11-2014 09:50 AM |
Torque App - 100% Accurate Fuel Remaining | B-R-Z | Engine, Exhaust, Transmission | 0 | 08-29-2014 04:16 PM |