Please Help!!! Limp Mode 4th Gear C7 Corvette A8
Thread Starter
Navigator
Joined: Dec 2017
Posts: 9
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Please Help!!! Limp Mode 4th Gear C7 Corvette A8
So I snapped my input shaft on my transmission. I got that repaired. Once we turned on the car I got a CEL so I immediately turned it off then the code it threw was P07BF - input speed sensor circuit low voltage .. so we took off the tranny again and changed the only sensor that we thought was it which was the Output speed sensor.. put it back together and nope still same problem and throws the CEL and 4th Gear Limp Mode... called the dealership to see once again if they had a Input speed sensor and nope they said the C7 don’t have one other then the Output sensor and speed sensors on the wheels (called 3 different dealers) please help!!!
mods:
Texas Speed headers & X pipe
E85 Fuel
Cam & Cam kit
Hp Tuners tune
AFM delete etc ...
mods:
Texas Speed headers & X pipe
E85 Fuel
Cam & Cam kit
Hp Tuners tune
AFM delete etc ...
Instructor
Joined: Mar 2013
Posts: 102
Likes: 15
From: ocala fl
So I snapped my input shaft on my transmission. I got that repaired. Once we turned on the car I got a CEL so I immediately turned it off then the code it threw was P07BF - input speed sensor circuit low voltage .. so we took off the tranny again and changed the only sensor that we thought was it which was the Output speed sensor.. put it back together and nope still same problem and throws the CEL and 4th Gear Limp Mode... called the dealership to see once again if they had a Input speed sensor and nope they said the C7 don’t have one other then the Output sensor and speed sensors on the wheels (called 3 different dealers) please help!!!
mods:
Texas Speed headers & X pipe
E85 Fuel
Cam & Cam kit
Hp Tuners tune
AFM delete etc ...
mods:
Texas Speed headers & X pipe
E85 Fuel
Cam & Cam kit
Hp Tuners tune
AFM delete etc ...
Drifting
Joined: May 1999
Posts: 1,370
Likes: 12
From: Garwood NJ
So I snapped my input shaft on my transmission. I got that repaired. Once we turned on the car I got a CEL so I immediately turned it off then the code it threw was P07BF - input speed sensor circuit low voltage .. so we took off the tranny again and changed the only sensor that we thought was it which was the Output speed sensor.. put it back together and nope still same problem and throws the CEL and 4th Gear Limp Mode... called the dealership to see once again if they had a Input speed sensor and nope they said the C7 don’t have one other then the Output sensor and speed sensors on the wheels (called 3 different dealers) please help!!!
mods:
Texas Speed headers & X pipe
E85 Fuel
Cam & Cam kit
Hp Tuners tune
AFM delete etc ...
mods:
Texas Speed headers & X pipe
E85 Fuel
Cam & Cam kit
Hp Tuners tune
AFM delete etc ...
Thread Starter
Navigator
Joined: Dec 2017
Posts: 9
Likes: 0
Safety Car
Joined: Aug 2012
Posts: 3,960
Likes: 1,106
All of this sensor data runs to the TCM so check the main harness connector itself at the transmission (and at the TCM if you unplugged it there) to make sure a contact wasn't damaged during connector install. Of course the separate sensor harness connectors could also be the problem.
You may find the photos and information here useful: http://www.atra.com/Webinars/GM/8L90_Introduction.pdf
You may find the photos and information here useful: http://www.atra.com/Webinars/GM/8L90_Introduction.pdf
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Thread Starter
Navigator
Joined: Dec 2017
Posts: 9
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No fix yet bummer
All of this sensor data runs to the TCM so check the main harness connector itself at the transmission (and at the TCM if you unplugged it there) to make sure a contact wasn't damaged during connector install. Of course the separate sensor harness connectors could also be the problem.
You may find the photos and information here useful: http://www.atra.com/Webinars/GM/8L90_Introduction.pdf
You may find the photos and information here useful: http://www.atra.com/Webinars/GM/8L90_Introduction.pdf
Been two months already and no fix yet//:Havnt found the solution ....
Drifting
Joined: Apr 2015
Posts: 1,276
Likes: 317
Something else not right, and you can bet it's related to the input shaft failure or it's replacement. Something has been overlooked, be it unseen damage or faulty component replacement. I do feel your pain, I would like to see components if you tear it down again.
Thread Starter
Navigator
Joined: Dec 2017
Posts: 9
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Thread Starter
Navigator
Joined: Dec 2017
Posts: 9
Likes: 0
Update
So yes, the transmission is getting tear down once again and hopefully they find something