AFR too lean
Team Owner
Joined: May 2006
Posts: 21,473
Likes: 356
From: Palmdale, Ca----- 2009 Cyber Gray 4LT A6 F55 452 RWHP 422 RWTQ- RIP 1998 C5 734 RWHP & 585 RWTQ-----
Go to Ballenger Motorsports for your O2 sensor
https://www.bmotorsports.com/shop/in...n0rlgeck0gd601
Thanks, Matt
Last edited by madmatt9471; Apr 24, 2021 at 03:59 PM.
Team Owner
Joined: May 2006
Posts: 21,473
Likes: 356
From: Palmdale, Ca----- 2009 Cyber Gray 4LT A6 F55 452 RWHP 422 RWTQ- RIP 1998 C5 734 RWHP & 585 RWTQ-----
Thread Starter
Drifting
Joined: Apr 2013
Posts: 1,501
Likes: 185
From: Erie PA
The AEM set up was installed last spring with my SC kit. Its the 4.9 version
Plugs were also installed at the same time. Gune hasn't changed ... base tune that was flashed by A&A that served great all last summer.
my stft and ltft definitely need adjustment..... no change since install and flash
going to check air filter as I need to clean it anyway as regular maintenance.
I did NOT use any stabilizer this year and never started it over winter
it was covered in my heated garage with cover and battery tender.
Today I took it to autozone (about 2 miles away).... at start up, it was at 14.7 ..... after ie for a few minutes it was 15.6. Slightly hesitate and sputter SOMETIMES when stepping on throttle at low rpm.
on the way home it seemed more normal (14.6-15.8) at cruise curious I think it is fluctuating more than it used to.
I just need to do some logging.
Plugs were also installed at the same time. Gune hasn't changed ... base tune that was flashed by A&A that served great all last summer.
my stft and ltft definitely need adjustment..... no change since install and flash
going to check air filter as I need to clean it anyway as regular maintenance.
I did NOT use any stabilizer this year and never started it over winter
it was covered in my heated garage with cover and battery tender.Today I took it to autozone (about 2 miles away).... at start up, it was at 14.7 ..... after ie for a few minutes it was 15.6. Slightly hesitate and sputter SOMETIMES when stepping on throttle at low rpm.
on the way home it seemed more normal (14.6-15.8) at cruise curious I think it is fluctuating more than it used to.
I just need to do some logging.
Thread Starter
Drifting
Joined: Apr 2013
Posts: 1,501
Likes: 185
From: Erie PA
Today decided to drive it to work. Fine at start up, but Its running rich after about 5 minutes. Sitting at red light at idle it will be at 10.6... and a little rough and definitelysmells rich from exhaust. The wideband seems to be accurate.
I'm going to have to check the upstream o2's.
Ordered new ones just in case. Are original from 2006 and 54k miles.
I'm going to have to check the upstream o2's.
Ordered new ones just in case. Are original from 2006 and 54k miles.
Team Owner
Joined: May 2006
Posts: 21,473
Likes: 356
From: Palmdale, Ca----- 2009 Cyber Gray 4LT A6 F55 452 RWHP 422 RWTQ- RIP 1998 C5 734 RWHP & 585 RWTQ-----
Today decided to drive it to work. Fine at start up, but Its running rich after about 5 minutes. Sitting at red light at idle it will be at 10.6... and a little rough and definitelysmells rich from exhaust. The wideband seems to be accurate.
I'm going to have to check the upstream o2's.
Ordered new ones just in case. Are original from 2006 and 54k miles.
I'm going to have to check the upstream o2's.
Ordered new ones just in case. Are original from 2006 and 54k miles.
I had this happen on my C5 but it was only on one bank (passenger side) and it fouled out the entire set of plugs -
I decided to change both O2's and it solved all the issues I was having
I look forward to seeing the results
Thanks,Matt
Thread Starter
Drifting
Joined: Apr 2013
Posts: 1,501
Likes: 185
From: Erie PA
replaced the upstream o2's and took it for a ride. got about a mile from home and sitting at a red light , it started sputtering and stalling .... afr was showing very rich. stepped on the gas and barely stayed running . got around the corner and it sputtered for a few seconds (aomost stalled completely) and them started running again. but definitely wasn't running correctly.....managed to get home and AFR was about 13.5.
Today I hooked up the laptop via HP tuners and went for a 3-4 mile drive while logging. AFR was around 17.6 under normal cruising conditions.
unfortunately, i accidently clicked the wrong button and didn't get a chance to save the log. although the car didn't run too poorly the AFR is NOT right.
I'm going to do another log and SAVE it this time. I want to get it running the way it was to ensure there are no issues before I take it to get it tuned
sucks trying to find the time to work on it between work and other life priorities. LOL
Today I hooked up the laptop via HP tuners and went for a 3-4 mile drive while logging. AFR was around 17.6 under normal cruising conditions.
unfortunately, i accidently clicked the wrong button and didn't get a chance to save the log. although the car didn't run too poorly the AFR is NOT right.
I'm going to do another log and SAVE it this time. I want to get it running the way it was to ensure there are no issues before I take it to get it tuned
sucks trying to find the time to work on it between work and other life priorities. LOL
Thread Starter
Drifting
Joined: Apr 2013
Posts: 1,501
Likes: 185
From: Erie PA
Hooked scanner up today and reset all codes.
At idle (in garage) I was logging and didn't notice anything that seemed too obvious.
just to troubleshoot, unplug MAP and instant change as expected. Replaced plug and unplugged MAF... no noticeable change in running, barely registered on log.
Also, disconnected vacuum line near firewall (by driver side fuel rail) and no noticeable change and no vacuum
Have the following codes:
p0030
P0050
p0134
p0135
p0154
P0155
I've already changed o2 sensors with brand new ones.
I did find that the driver side extension wire was laying on headers.... plastic looming around was melted but wires were not, they looked charged a bit(discolored) but not broken and no bare wires.
The passenger side is fine....
If it were the wire on driver side, wouldn't it just get codes on ONE bank?
At idle (in garage) I was logging and didn't notice anything that seemed too obvious.
just to troubleshoot, unplug MAP and instant change as expected. Replaced plug and unplugged MAF... no noticeable change in running, barely registered on log.
Also, disconnected vacuum line near firewall (by driver side fuel rail) and no noticeable change and no vacuum
Have the following codes:
p0030
P0050
p0134
p0135
p0154
P0155
I've already changed o2 sensors with brand new ones.
I did find that the driver side extension wire was laying on headers.... plastic looming around was melted but wires were not, they looked charged a bit(discolored) but not broken and no bare wires.
The passenger side is fine....
If it were the wire on driver side, wouldn't it just get codes on ONE bank?
Corvette Stories
The Best of Corvette for Corvette Enthusiasts
5 Best & 5 Worst Corvette Daily Drivers
Joe Kucinski
The Headlights of Every Corvette Generation Explained
Joe Kucinski
5 Best & 5 Most Overrated Corvette Track Packages of All Time!
Joe Kucinski
Every 2027 Corvette Engine Explained
Joe Kucinski
Designer Imagines A Corvette That Looks More Like a Corvette Than the Corvette
Verdad Gallardo
10 Ugly Corvettes That We Still Kinda Love
Joe Kucinski
Top 10 Most Expensive Corvettes Ever Sold on Bring A Trailer
Brett Foote
10 Things Every Corvette Owner Needs (2026 Edition)
Michael S. Palmer
8 Most "Only Corvette Owners Understand" Quirks and Problems
Pouria Savadkouei
Thread Starter
Drifting
Joined: Apr 2013
Posts: 1,501
Likes: 185
From: Erie PA
PROBLEM SOLVED!!!!!
After more research and tracing, found that fuse #6 in fuse box under hood was blown.
The wires on the header must have been just enough to short and blow fuse....which controls BOTH o2 banks. Replaced fuse and afr is 14.7-15.1 and running. much smother at idle!
After more research and tracing, found that fuse #6 in fuse box under hood was blown.
The wires on the header must have been just enough to short and blow fuse....which controls BOTH o2 banks. Replaced fuse and afr is 14.7-15.1 and running. much smother at idle!
Last edited by hmmmm16417; May 14, 2021 at 09:59 PM.
Team Owner
Joined: May 2006
Posts: 21,473
Likes: 356
From: Palmdale, Ca----- 2009 Cyber Gray 4LT A6 F55 452 RWHP 422 RWTQ- RIP 1998 C5 734 RWHP & 585 RWTQ-----
PROBLEM SOLVED!!!!!
After more research and tracing, found that fuse #6 in fuse box under hood was blown.
The wires on the header must have been just enough to short and blow fuse....which controls BOTH o2 banks. Replaced fuse and afr is 14.7-15.1 and running. much smother at idle!
After more research and tracing, found that fuse #6 in fuse box under hood was blown.
The wires on the header must have been just enough to short and blow fuse....which controls BOTH o2 banks. Replaced fuse and afr is 14.7-15.1 and running. much smother at idle!
This will really help others out -
Thanks,Matt
Race Director
Joined: May 2004
Posts: 16,667
Likes: 1,209
From: Raleigh, NC
St. Jude Donor '15
FYI, HPTuners automatically saves all logs to a folder in my documents, hptuners. I think it's under my documents, hptuners, scanner then logs but you may have to look around a little bit. I don't have it in front of me.
Thread Starter
Drifting
Joined: Apr 2013
Posts: 1,501
Likes: 185
From: Erie PA
I thought it would have saved it , but I couldn't find it . the only logs I saw were ones I made last year right after my install. Maybe the default folder is changed somehow. I'm still new to the whole HP tuners thing. so much info and so many screens, will take a lot of tinkering to get familiar.
I have all the tuning books on PDF and printed hard copies , just haven't had a lot of time to play with it. not to mention that I fear screwing stuff up LOL