Posted by Traveler on November 10, 19100 at 09:32:57:
In Reply to: Re: Diff Talk posted by rgv on November 10, 19100 at 09:02:33:
GM was playing with E-cells when I was there in the early 80's. The idea was the open loop calibrations needed to be changed somewhat after the engine had 50K miles. The e-cell was basically an hour meter that eventually opened up a conductor through electroplating, and the flag was an input to the ECM. The ECM would them apply a correction factor to the calibrations.
I was never involved with them and I think they were only used on a few models in the '80s. One of the problems with the concept was if the ECM was swapped out, the e-cell had to start from scratch no matter how many miles were on the engine. Likewise a reconditioned ECM would require a new e-cell. I think the idea was abandoned.
GM now has the capability to adjust what open loop calibrations are downloaded into the flash memory based on the mileage of the vehicle. I have no idea whether they use this appraoch, but it would eliminate the e-cell. My guess is the control algorithms are good enough that only one version of open loop calibrations are needed for the life of the engine.
Sharp eye you have to spot this obscure device.
All GM needs to do is use their oil change algorithm to limit the engine torque over the early life of the drive train for proper break in. Ideally it could be reactivated if major drive train repairs were performed, then would "expire". Any patent lawyers on the forum?