Check Engine Light - Please Help
Thread Starter
5th Gear
Joined: Aug 2024
Posts: 5
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From: Sacramento, CA
Check Engine Light - Please Help
Hello everyone, thanks for allowing me to join your site. I'll get straight to my issue.
I have a 2016 Stingray. The car sat in my garage for 12 months with a trickle charger. I recently took it to get smogGed, at which point it did not pass. Technicians told me to drive the car 100 miles and bring it back. 5 minutes after leaving the smog station, the CEL came on. I connected an OBD scanner to the car and the following 2 codes came up, P26C8 and P0711. After some research, I figured it was either the TFT Sensor, Wiring Harness, or a confused computer that was still hibernating from a very long winters nap. I decided to drive the car around for about 30 minutes at varying speeds/conditions. I hooked the scanner up again, but this time the codes were P26C8 and P12FD (Exhaust Flow Valve Stuck Open Bank 2). But why am I getting different codes?? And now the P0711 isn't coming up. What might be causing this? Should I continue to drive the car more so the computer can finish doing everything it needs to do? PLEASE HELP!! THANK YOU
I have a 2016 Stingray. The car sat in my garage for 12 months with a trickle charger. I recently took it to get smogGed, at which point it did not pass. Technicians told me to drive the car 100 miles and bring it back. 5 minutes after leaving the smog station, the CEL came on. I connected an OBD scanner to the car and the following 2 codes came up, P26C8 and P0711. After some research, I figured it was either the TFT Sensor, Wiring Harness, or a confused computer that was still hibernating from a very long winters nap. I decided to drive the car around for about 30 minutes at varying speeds/conditions. I hooked the scanner up again, but this time the codes were P26C8 and P12FD (Exhaust Flow Valve Stuck Open Bank 2). But why am I getting different codes?? And now the P0711 isn't coming up. What might be causing this? Should I continue to drive the car more so the computer can finish doing everything it needs to do? PLEASE HELP!! THANK YOU
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From: Hartford WI
Hello everyone, thanks for allowing me to join your site. I'll get straight to my issue.
I have a 2016 Stingray. The car sat in my garage for 12 months with a trickle charger. I recently took it to get smogGed, at which point it did not pass. Technicians told me to drive the car 100 miles and bring it back. 5 minutes after leaving the smog station, the CEL came on. I connected an OBD scanner to the car and the following 2 codes came up, P26C8 and P0711. After some research, I figured it was either the TFT Sensor, Wiring Harness, or a confused computer that was still hibernating from a very long winters nap. I decided to drive the car around for about 30 minutes at varying speeds/conditions. I hooked the scanner up again, but this time the codes were P26C8 and P12FD (Exhaust Flow Valve Stuck Open Bank 2). But why am I getting different codes?? And now the P0711 isn't coming up. What might be causing this? Should I continue to drive the car more so the computer can finish doing everything it needs to do? PLEASE HELP!! THANK YOU
I have a 2016 Stingray. The car sat in my garage for 12 months with a trickle charger. I recently took it to get smogGed, at which point it did not pass. Technicians told me to drive the car 100 miles and bring it back. 5 minutes after leaving the smog station, the CEL came on. I connected an OBD scanner to the car and the following 2 codes came up, P26C8 and P0711. After some research, I figured it was either the TFT Sensor, Wiring Harness, or a confused computer that was still hibernating from a very long winters nap. I decided to drive the car around for about 30 minutes at varying speeds/conditions. I hooked the scanner up again, but this time the codes were P26C8 and P12FD (Exhaust Flow Valve Stuck Open Bank 2). But why am I getting different codes?? And now the P0711 isn't coming up. What might be causing this? Should I continue to drive the car more so the computer can finish doing everything it needs to do? PLEASE HELP!! THANK YOU
Thread Starter
5th Gear
Joined: Aug 2024
Posts: 5
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From: Sacramento, CA
Hi aklim, the car did not pass smog due to the OBD II. I mentioned the car had been sitting for a year so the techs told me to drive it 100 miles and bring it back. I never disconnected the battery. I had purchased a new battery a month before it sat for the year, but I kept that battery on the charger the entire time. The day I took it to get smogged, I put fresh gas in it, then drove straight to the smog station. I realize I should have driven the car much more before doing that. The battery has been fine since taking it off the charger on 8/24 in the morning. But maybe the computer needs to go through a checklist of things first, which can only happen after the vehicle has been driven more? I don't know. Thanks for the reply 
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Joined: Feb 2023
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The ecu takes a certain amount of drive cycles before all the obd2 monitors read as ready. Drive the car 50 miles somewhere. Shut it off. Restart it and then drive back and you should be ready for a obd2 scan. Clear the codes before you go and see if any come back after. Just dont clear them after the drive otherwise you'll need to do a couple more drive cycles to get them back to ready.
Thread Starter
5th Gear
Joined: Aug 2024
Posts: 5
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From: Sacramento, CA
The ecu takes a certain amount of drive cycles before all the obd2 monitors read as ready. Drive the car 50 miles somewhere. Shut it off. Restart it and then drive back and you should be ready for a obd2 scan. Clear the codes before you go and see if any come back after. Just dont clear them after the drive otherwise you'll need to do a couple more drive cycles to get them back to ready.
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From: Hartford WI
Hi Lux, that makes sense from what I've been reading and what the smog techs told me. I've tested the battery and it's good. The codes will not clear through the scanner though, so I'll clear them by disconnecting the battery. Then I'll take a road trip with her and fingers crossed the CEL doesn't come back. Thanks for all the advice!
Thread Starter
5th Gear
Joined: Aug 2024
Posts: 5
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From: Sacramento, CA
After the CEL came on, I took it to AutoZone (Down the street from the smog station). Connected their scanner and that's when the codes P26C8 & P0711 came up. I had them test the battery as well, which came back fine. The next day I went back to AutoZone to see if their scanner could clear the codes, which it wouldn't. So I bought a scanner there that would. I hooked it up in the parking lot and that's when codes P26C8 and P12FD came up, but not P0711. I tried clearing the codes with the scanner I just purchased, only to learn that it couldn't due to the type of code. Now I will try clearing the codes by disconnecting the battery for 15 minutes.
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From: Cape Coral, Florida
After the CEL came on, I took it to AutoZone (Down the street from the smog station). Connected their scanner and that's when the codes P26C8 & P0711 came up. I had them test the battery as well, which came back fine. The next day I went back to AutoZone to see if their scanner could clear the codes, which it wouldn't. So I bought a scanner there that would. I hooked it up in the parking lot and that's when codes P26C8 and P12FD came up, but not P0711. I tried clearing the codes with the scanner I just purchased, only to learn that it couldn't due to the type of code. Now I will try clearing the codes by disconnecting the battery for 15 minutes.
Thread Starter
5th Gear
Joined: Aug 2024
Posts: 5
Likes: 0
From: Sacramento, CA
These DTC's will NOT clear because they are stored in "Mode 10" in your scan tool...I'm not going to explain Mode 10 this right now but you can Google it...these are permanent codes and will not clear until those issues are fixed and the car had run and completed a drive cycle...Mode 10 was fully implemented in 2013 for any car....disconnecting the battery will not work.
