Resetting your C5 Corvette's PCM
Le Mans Master
Joined: Sep 2006
Posts: 6,050
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From: Phoenix AZ
2021 C4 of the Year - Modified Finalist
speedometer
Also, I was told that the 4 wheel speed sensors are monitored by the pcm and is a check for the vss.
(same theory as a cam position sensor is monitored along with the crank position sensor for engine speed, timing, valve event and fuel administration)
(same theory as a cam position sensor is monitored along with the crank position sensor for engine speed, timing, valve event and fuel administration)
Team Owner
Joined: May 2004
Posts: 26,345
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From: SoCal
Originally Posted by JR_VETTE
No such thing as a dumb question!
The permanent tune contains the 'baseline' for the various parameters. Ie. injector flow rate, VE table (engines ability to fill the cylinders), MAF calibration data, spark tables, etc. As you drive, the PCM can to a point adjust some of the settings to meet optimal settings within reason. When you turn the car off, those 'adjusted' parameters are stored in non-volitile memory which is saved until power to the PCM is removed, or they are cleared via a TECH2, HP Tuners, etc.
I guess the answer to your question is the PCM doesn't really tune out the default settings. It just adjusts *some* of the parameters to make the car happy. The reason we tune is to adjust the default parameters to make the car happier (advance WOT timing, lean out the WOT from the factory pig rich setting, adjust the cooling fans on/off temps, etc). The PCM can only adjust the permanent settings to a point. When you tune a car, you are writing a permanent set of data that can't be erased by pulling power to the battery.
The permanent tune contains the 'baseline' for the various parameters. Ie. injector flow rate, VE table (engines ability to fill the cylinders), MAF calibration data, spark tables, etc. As you drive, the PCM can to a point adjust some of the settings to meet optimal settings within reason. When you turn the car off, those 'adjusted' parameters are stored in non-volitile memory which is saved until power to the PCM is removed, or they are cleared via a TECH2, HP Tuners, etc.
I guess the answer to your question is the PCM doesn't really tune out the default settings. It just adjusts *some* of the parameters to make the car happy. The reason we tune is to adjust the default parameters to make the car happier (advance WOT timing, lean out the WOT from the factory pig rich setting, adjust the cooling fans on/off temps, etc). The PCM can only adjust the permanent settings to a point. When you tune a car, you are writing a permanent set of data that can't be erased by pulling power to the battery.
DH
Race Director
Joined: Apr 2001
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From: Saint Augustine, FL
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Originally Posted by Dirty Howie
So if you do the reset on a "tuned" car you go back to original "tuned" settings....right??
DH
DH
Remember though, the PCM will still adjust some of those 'tuned' parameters slightly (mainly your Air/Fuel while in closed loop), so you'll still need to drive around for a little while, while the PCM 'learns'.
Race Director
Joined: Apr 2001
Posts: 19,329
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From: Saint Augustine, FL
Mid-TN Events Coordinator
St. Jude Donor '03-'04-'05-'06-'07-'08-'09-'10-'11-'12-'13-'14-'15-'16
Originally Posted by General Lee
Will removing these fuse clear stored cel's i cleared them through my scan tool but i still have a yellow(failure) IM rediness light. CEL P0101.
Other than that, I don't know what to tell you. Regardless, it's a MAF failure of some sort.
Pro
Joined: Oct 2006
Posts: 551
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From: N.J.
Originally Posted by JR_VETTE
That's a MAF failure of some sort. I would take a look at the connector and the sensor itself. Do you have a aftermarket oiled airfilter? If so, it might have been over oiled and gotten on the maf sensor.
Other than that, I don't know what to tell you. Regardless, it's a MAF failure of some sort.
Other than that, I don't know what to tell you. Regardless, it's a MAF failure of some sort.
I do have a K+N filter not new or freshly oiled though, i know i can clean the wire just have to get the cleaner first. and I'll check the connecter to thanks.
