so, if you have regular in your tank and fill it up super, assuming you don't disconnect the battery, how long before the computer resets the engine to best horsepower?
I'm assuming you'd have to press the engine to get it to advance, the computer would see no tendancy to knock and adjust accordingly
I would also guess this would take quite a few hard excellerations
or, as someone suggested, does the computer default to "best performance" whenever you start the car and adjust down according to knock?
so, if you have regular in your tank and fill it up super, assuming you don't disconnect the battery, how long before the computer resets the engine to best horsepower?
I'm assuming you'd have to press the engine to get it to advance, the computer would see no tendancy to knock and adjust accordingly
I would also guess this would take quite a few hard excellerations
or, as someone suggested, does the computer default to "best performance" whenever you start the car and adjust down according to knock?
Engine controllers don't learn when under WOT. The learning you refer to are the adaptives which are low to midrange loading offsets. All that a higher octane would give you is less tendency to knock.
So to answer your how long question ... Just disconnect the negative side of the battery or pull the two fuses (42 & 43) for the ECM for 30 minutes and your all set.
__________________ #118042 11/18/06 GXP Mean Darkside loaded wo On-Star
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So to answer your how long question ... Just disconnect the negative side of the battery or pull the two fuses (42 & 43) for the ECM for 30 minutes and your all set.
mike, I understand that, but if you don't disconnect the electricity, how long before the computer does it ?
Engine controllers don't learn when under WOT. The learning you refer to are the adaptives which are low to midrange loading offsets. All that a higher octane would give you is less tendency to knock.
this isn't what I've learned
I've learned that the computer will not advance as far when it detects knocking and the computer goes into differant logistics to keep te engine healthy
so, if the enjine is in a differant logistic, it would never know the engine can accept further advance unless you pushed the engine to the respective maximum advance
if you never drove your car hard then the engine would never see that it can advance as far as it could with higher octane
seems to me the best scenario would be that every time you start the car the computer derfaults to "best performance" and adjusts against that rather then setting itself and needed to re detect
~~~~~~~~~~~~~~~~~~~ Pontiac builds excitement... Saturn has rethought it's image...
The time has come for the enthusiasts... NASSOA
Founding Member - Recording Secretary - Northeast ~~~~~~~~~~~~~~~~~~~
Think that most have reported that you are looking at a couple of tanks ...
someone should be able to get the actual data from the solstice team telling us exactly what the computer looks at, maybe small dealer can find out
the computer has to somehow find out it can advance the engine more...the only way to see that is if the engine goes to deepest advance...so to me it wouldn't be an amount of gallons it would be how hard the car is driven
it might be as simple as removing the gas cap though...I'd love to find out
I've learned that the computer will not advance as far when it detects knocking and the computer goes into differant logistics to keep te engine healthy
so, if the enjine is in a differant logistic, it would never know the engine can accept further advance unless you pushed the engine to the respective maximum advance
if you never drove your car hard then the engine would never see that it can advance as far as it could with higher octane
seems to me the best scenario would be that every time you start the car the computer derfaults to "best performance" and adjusts against that rather then setting itself and needed to re detect
Perris:
THe wot operation is a fixed set of values residing in a matrix within the ECU. These values are only modified by ECT, IAT and altitude. Many tuners (not all) who cannot explain to a customer why they are not getting the projected hp, explain it away by say "wait till the computer relearns" . No matter what you have heard the ECU does not modify the wot parameters. Like Fast Mike, said you can pull the fuses and the STFT and LTFT (injectior add/subtract parameters) will modify themselves quicker. When you do this it is a good rule is to initially drive the car over a good range of speeds and power.
You don't get higher hp with a higher octane with the OEM ECU. The only way the hp will increase is when you add timing at wot and due to liability the manufacturers will not do that. You could lose hp on a car with knock retard if you used an octane level lower than recommended. The ECU will pull timing when the knock sensors fire. This is not totally true on the GXP, it runs at a low advance value during wot and would respond to knock by enriching the a/f during closed loop.
Another, issue is that in many cases the knock sensors are pulled from the circuit at wot, because they cannot differentiate the back ground noise from true detonation, I'm not sure about this on the Solstice. There is nothing magic about knock sensors, they are a microphone tuned to a narrow frequency.
THe wot operation is a fixed set of values residing in a matrix within the ECU. These values are only modified by ECT, IAT and altitude. Many tuners (not all) who cannot explain to a customer why they are not getting the projected hp, explain it away by say "wait till the computer relearns" . No matter what you have heard the ECU does not modify the wot parameters. Like Fast Mike, said you can pull the fuses and the STFT and LTFT (injectior add/subtract parameters) will modify themselves quicker. When you do this it is a good rule is to initially drive the car over a good range of speeds and power.
You don't get higher hp with a higher octane with the OEM ECU. The only way the hp will increase is when you add timing at wot and due to liability the manufacturers will not do that. You could lose hp on a car with knock retard if you used an octane level lower than recommended. The ECU will pull timing when the knock sensors fire. This is not totally true on the GXP, it runs at a low advance value during wot and would respond to knock by enriching the a/f during closed loop.
Another, issue is that in many cases the knock sensors are pulled from the circuit at wot, because they cannot differentiate the back ground noise from true detonation, I'm not sure about this on the Solstice. There is nothing magic about knock sensors, they are a microphone tuned to a narrow frequency.
Jack, that's good information, thanx
according to what you are saying the engine doesn't set new peramertes because the engine heard some knock, it's a "per knock" pullback
the computer simply pulls advance back if there's a knock, if there's no knock it continues normal perameters
if this si true, there is no "three tanks", there is no "removing the battery ground" or taking out any fuse
the computer simply pulls advance back or doesn't pull the advance back according to whether or not there is knock
so this "disconnect the battery" stuff is a myth according to your information
this to me would be the best design, setting new perameters according to one or two early knocks would make no sense to me
there is a lot of urban legend to the "learn" thing, but, after you add a mod the learning does take place for the closed loop. I have done some serious mods on other cars where you absolutely have to clean the ECU, otherwise the low speed driveability was terrible.
As far as knock retard at WOT, I don't know if it exists on the Solstice. Some manufacturers only utilize it in closed loop. I can tell you this on the GXP, they don't pull timing at WOT, the timing for that perfect combustion point (15 deg ATDC) is controlled by the a/f, therefore, they would force rich, if they sensed a problem.
got it jack, it's not a timing pull back it's a mixture pull back
now if the computer changes mixture when it senses a problem, that would be on a need to do situation, not a per tank or per gallon thing...it simply forces a change in mixture to prevent damage when it hears knock...a new tank of higher octane would give immediate result without disconnecting anything or pulling any fuse
I understand mods add some learn factor, but when we are talking about gas, it doesn't look like there is any learn at all...high octane tank would need no learning, no disconnect of electricity, the computer would simply run at whatever setting according to the respective grade octane with each respective wide open throttle
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