Crank position relearn
Thread Starter
Drifting
Joined: May 2005
Posts: 1,590
Likes: 1
From: Littleton Colorado
Crank position relearn
Can this be done with any of the consumer or hand held tuner devices such as a preditor? How hard is this to do for someone who is not a mechanic?
:o I thought an option of buying a PCM from a mail order tuner was a good idea, until I got the PCM and the instructions said I needed to do a crank position relearn
I had not heard of this before, but I have now seen some mention of it in the archives.Any words of advice beyond take it to a real mechanic?
Le Mans Master
Joined: Jan 2001
Posts: 5,786
Likes: 6
From: Lafayette Colorado
I believe that the "Crank Position Relearn" procedure requires the use of the Tech II device. Useless the crank has actually been removed, there should be no need to do the procedure for swapping out the PCM. Granted that PCM with have to learn its new setup( LTFT, idle relearn, and so forth ), but all can be done without the need of Tech II.
Keith
Keith
Uber Waxer
Joined: May 2004
Posts: 8,651
Likes: 5
From: Hanover MD
Cruise-In 8-9-10-11 Veteran
CI 9, 10 & 11 Car Show Winner
St. Jude Donor '08-'10
Originally Posted by ArKay99
Actually, You only need the scanner to do this. I think EFILive version 6 also has this.i have v5.0 with the pro cable, so im sure the newer ones have incorporated it in.
Le Mans Master
Joined: Jul 2002
Posts: 7,370
Likes: 8
From: Slave to the evil empire
Cruise-In V Veteran
St. Jude Donor '04
Originally Posted by kromberg
I believe that the "Crank Position Relearn" procedure requires the use of the Tech II device. Useless the crank has actually been removed, there should be no need to do the procedure for swapping out the PCM. Granted that PCM with have to learn its new setup( LTFT, idle relearn, and so forth ), but all can be done without the need of Tech II.
Keith
Keith
Le Mans Master
Joined: Jan 2001
Posts: 5,786
Likes: 6
From: Lafayette Colorado
Originally Posted by FFR-Z06
The PCM also needs to know what position the crank is at so that it can fire the plugs and injectors at the right time which is why the relearn procedure needs to be done.
Keith
Corvette Stories
The Best of Corvette for Corvette Enthusiasts
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
10 Reasons the C6 Z06 is Still A Performance Benchmark After 20 Years
Joe Kucinski
How Much Horsepower Every Corvette Engine "LOST" in 1972
Joe Kucinski
Top 10 DOs and DON'Ts for Protecting Your Convertible Top!
Michael S. Palmer
Top 10 Most Explosive Corvettes Ever Made: Power-to-Weight Ratio Ranked!
Joe Kucinski
150 hp to 1,250 hp: Every Corvette Generation Compared by the Specs That Matter
Joe Kucinski
8 Coolest Corvette Pace Cars (and Replicas) of All Time
Verdad Gallardo
Safety Car
Joined: Sep 2003
Posts: 3,558
Likes: 2
From: Cape Coral FL
Originally Posted by MattB
Thanks for the input, the directions state that the relearn needs to be done so the PCM can detect a miss-fire does that make sense? Anyone with experience in swaping PCMs?
does that make sense? Anyone with experience in swaping PCMs? Yes, it's the main way the PCM detects a misfire.
Uber Waxer
Joined: May 2004
Posts: 8,651
Likes: 5
From: Hanover MD
Cruise-In 8-9-10-11 Veteran
CI 9, 10 & 11 Car Show Winner
St. Jude Donor '08-'10
Originally Posted by MattB
Thanks for the input, the directions state that the relearn needs to be done so the PCM can detect a miss-fire does that make sense? Anyone with experience in swaping PCMs?
does that make sense? Anyone with experience in swaping PCMs? yes, but hopfully whoever tuned your pcm didnt turn missfire detection off. you must have that enabled to do a crank relearn
Melting Slicks
Joined: Jun 2004
Posts: 3,439
Likes: 6
From: Newark, DE
St. Jude Donor '06
I just had my PCM replaced and had to do a crank position relearn after. There may be other ways of accomplishing it, but the shop used a Tech2, set it to the appropriate menu and then floored it twice while idling in Neutral - POSITION SENSOR LEARNED.
Melting Slicks
Joined: Feb 2001
Posts: 2,804
Likes: 358
From: Northville, MI
Any scan tool with the enhanced GM pids and a bidirectional cable will perform the CASE Learn. Anytime you replace the PCM you need to have it done. Another alternative is an Auto Labs type of shop, they usually charge $30-45
Thanks everyone. 
