How exactly does the ECU work?
How exactly does the ECU work?
I know basically what the ECU does, but how exactly does one work? The ECU in the G35 (and I am assume that most cars are the same) has the capability to be reset and sort of learn the driving style of the driver. How exactly does the ECU do this? Is it just a computer chip that has memory that will remember the driving style and then work accordingly?
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Q45tech
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- Car: 1990 Q45 342,400 miles 22 years ownership with original engine
1995 G20t 5 speed 334,000 miles 16" 2002 wheels - 205/50/16 Sr20ve vvl
Lot of this is marketing hype! !!!!!!!!!!!!!!!!
Except that newer O2 sensors are more wide band [instead of just working at cruise] they can report a rough approximation of a richer mixture and the ecu works faster and has more memory so it can solve equation in almost real time.........whereas old OBD1 was pretty limited to looking up WOT and maybe trimming the table by the MAF voltage within a narrow 20% range.
Memory of how many WOT per mile could set a flag to shift more aggressively and not worry so much about smoothness.......kind of like the power economy switch on Toyota.........maybe there are 3-4 programs and what you do [have done] with throttle is remembered [learned].
Another area is acceleration enrichment plus tip in throttle timing pull out........they can make the car feel a little more aggressive by wasting more fuel during acceleration.
The 1990 Q had adaptive ecu and tcu.........in that shifts were a function of ATF temperature and TPS voltage; ecu looked at MAF all the way to redline and ignition advance was reduced with AC on signal and excessive coolant temp............rough and dirty but adaptive to the way driver behaved.
It makes me laugh at all the ecu resetting threads on other G35 forums.
Except that newer O2 sensors are more wide band [instead of just working at cruise] they can report a rough approximation of a richer mixture and the ecu works faster and has more memory so it can solve equation in almost real time.........whereas old OBD1 was pretty limited to looking up WOT and maybe trimming the table by the MAF voltage within a narrow 20% range.
Memory of how many WOT per mile could set a flag to shift more aggressively and not worry so much about smoothness.......kind of like the power economy switch on Toyota.........maybe there are 3-4 programs and what you do [have done] with throttle is remembered [learned].
Another area is acceleration enrichment plus tip in throttle timing pull out........they can make the car feel a little more aggressive by wasting more fuel during acceleration.
The 1990 Q had adaptive ecu and tcu.........in that shifts were a function of ATF temperature and TPS voltage; ecu looked at MAF all the way to redline and ignition advance was reduced with AC on signal and excessive coolant temp............rough and dirty but adaptive to the way driver behaved.
It makes me laugh at all the ecu resetting threads on other G35 forums.
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elwesso
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2007 BMW M Coupe
2007 Infiniti G35 S 6MT - Location: Indiana
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I dont think that is what he is saying at all...
OBDII cars have more computing power (basically) and more memory... Thus, they have the ability to track driving habits over a longer period of the time (90-95 Q dont really have this at all)..... if you do mostly cruise and easy driving, it will set it for more of an economy mode rather than a high power mode...
The Q had more of a real time "memory" meaning that it adapts to how you are driving NOW, but yours may have more/less the ability to take in to consideration CURRENT and PAST driving habits...
I think that it may be mostly the placebo affect about resetting it.. I like to unplug my battery for a while, just because I get a lot of crazy electrical gremlins from time to time that are fixed by this method... However, erasing the memory cant do any harm.....
OBDII cars have more computing power (basically) and more memory... Thus, they have the ability to track driving habits over a longer period of the time (90-95 Q dont really have this at all)..... if you do mostly cruise and easy driving, it will set it for more of an economy mode rather than a high power mode...
The Q had more of a real time "memory" meaning that it adapts to how you are driving NOW, but yours may have more/less the ability to take in to consideration CURRENT and PAST driving habits...
I think that it may be mostly the placebo affect about resetting it.. I like to unplug my battery for a while, just because I get a lot of crazy electrical gremlins from time to time that are fixed by this method... However, erasing the memory cant do any harm.....