I suspect there's an internal battery just for the nav. similar to the types they have in PC's to keep the clock going. ...dean

Seattle 'Eastside' area
'R' Order - IP/Graphite 6MT Coupe; Prem., Nav. & XM [img]/w3timages/icons/smile.gif[/img]

 

Can anyone tell me why this would work? I mean, by disconnecting the battery for several hours, you are, in effect, doing a hard reboot or hard reset. BUT....what, software-wise is changing from the reboot??? Why would a hard reset make everything run better since, in essence, you are just rebooting the same software with all of its parameters.

If this works as good as you guys say then great! I'm all for it. But, if it does work....WHY.....HOW????

 

Because you're cleaning the "run-time" adaptive memory. As you drive around normal instead of aggressive, it starts to soften up.. shift early, shift slower, etc. You wipe that out, and all it has to go on is the fact that the pedal is on the floor...

2003.5 G35 Sedan Desert Platinum/Graphite Premium/Sport/Aero/Nav/Winter

 

Well, I took a shot at timing the difference after resetting the ECU, but unfortunately I couldn't get to the track, so I had to borrow a GTech accelerometer instead. The good news is that, while these things are generally a bit off the actual time, they're usually off by a consistent amount each run so long as you keep them mounted in the same place at the same angle, so they're useful for comparisons.

So anyway, very (yawn) very early this morning, I grannied my G out to a remote and relatively flat spot on the freeway, waited until nobody was around, then did one 1/4 mile drag. After that, I pulled into a service area, disconnected my battery, held down my brake pedal for 60 seconds, played solitaire on my laptop for 15 minutes, then hooked everything back up and used my manumatic to keep the revs high while driving back to about the same spot for another run.

The two times:
grannied ECU: 14.424
reset ECU: 14.276

I'd say that's a sufficiently large difference. I should add that some of that gain is probably due to running colder on the second run, since I ran the first one after only a short rest from driving on the freeway for about 40 minutes (looking for a spot). There could also be some measurement error from the equipment in play, but that's usually no more than 0.1 seconds either way. At nearly 0.15 seconds, I think that's a safe enough margin to assume that there is at least some performance gain to be had by resetting the ECU, though I doubt it's that large.

The only problem is it's not going to last you very long unless you drive around at 5000 rpms all day getting 12 miles per gallon.

-Jack
Obsidian/graphite '03 Coupe premium nav