Crank Relearn after PCM Changes
TECH Senior Member
Joined: Apr 2002
Posts: 6,080
Likes: 17
From: So.Cal.
When I had this problem after a motor/PCM swap my car woudn't make any power, wouldn't rev over ~4000 RPM, trans ran in limp mode and it had an SES light on the dash. Instantly fixed with CPS relearn procedure...
While this SES code is designed to set when the PCM does not know the crank position and cannot accurately predict/detect misfires, that's only half the story. The rest of the story is how the car behaves when this code is set, especially A4 cars.
Rob (Bad30th)
While this SES code is designed to set when the PCM does not know the crank position and cannot accurately predict/detect misfires, that's only half the story. The rest of the story is how the car behaves when this code is set, especially A4 cars.
Rob (Bad30th)
TECH Senior Member
Joined: Apr 2002
Posts: 6,080
Likes: 17
From: So.Cal.
When I had this problem after a motor/PCM swap my car woudn't make any power, wouldn't rev over ~4000 RPM, trans ran in limp mode and it had an SES light on the dash. Instantly fixed with CPS relearn procedure...
While this SES code is designed to set when the PCM does not know the crank position and cannot accurately predict/detect misfires, that's only half the story. The rest of the story is how the car behaves when this code is set, especially A4 cars.
Rob (Bad30th)
While this SES code is designed to set when the PCM does not know the crank position and cannot accurately predict/detect misfires, that's only half the story. The rest of the story is how the car behaves when this code is set, especially A4 cars.
Rob (Bad30th)
The PCM always knows the crank position... the CKP reluctor wheel is fixed to the crank, it can never lose its position;
the CASE relearn measures the crank's rate of deceleration on fuel cutoff and stores it for future reference... by comparing each crank event against this the PCM can detect misfires.
TECH Fanatic
Joined: Mar 2011
Posts: 1,050
Likes: 2
From: Odessa, TX
I know it's an old thread but a local tuner told me the crank pos. be relearned by unplugging the harness to the sensor put the key to on position for a few seconds the. Turn key to off position and plug it back in. I was kinda skeptical about it since Iv searched and searched but found nothing about it without a scanner. Can anyone tell me if it works or he was bs-ing me.
I know it's an old thread but a local tuner told me the crank pos. be relearned by unplugging the harness to the sensor put the key to on position for a few seconds the. Turn key to off position and plug it back in. I was kinda skeptical about it since Iv searched and searched but found nothing about it without a scanner. Can anyone tell me if it works or he was bs-ing me.
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Teching In
Joined: Jun 2010
Posts: 26
Likes: 0
I have an LS2 in my RX7 and have the same code, part of the relearn procedure requires you to keep your foot on the brake, given that my brake pedal has no input to my PCU I am assuming I will not be able to do a relearn???
Teching In
Joined: Jun 2010
Posts: 26
Likes: 0
