Ecm memory loss
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Joined: Feb 2008
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Ecm memory loss
Yesterday after riding about 200 miles we stopped for lunch. When I got back on the bike turned the key on and pushed the start button, but the transmission was engaged, of course won't start, so I popped it in nutrel, pushed the start button again, started right up but idled about 3000 rpm for a few seconds then very rough idle. I even stalled it a couple of times when leaving. After going a few miles it started running normal and ran good the rest of the day. My question is, is possible for the ECM to temporarily loose its memory? Or what could cause this? 2007 FXDBI V.H. fuel pack, stage 1 air cleaner, V.H. Straight shots.
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Joined: Mar 2010
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From: Hudson Valley, NY
not possible for the ECM to have an issue, i've been told those never go bad. 
anyway not an EFI guy but i do know computers and the ECM is a computer. a typical computer holds information in volitale RAM so needs a constant power source to maintain information in volatile RAM. on a computer mother board this power source is a CMOS battery so if your computer loses time and date or other critical information in the BIOS resets that is because of a bad CMOS battery.
i have no clue if this is how it works for an ECM, but i would wager it does and i would say it's definitely possible for the ECM to lose memory and critical setup information if the info in volitale RAM gets reset because it loses its power trickle.
anyway not an EFI guy but i do know computers and the ECM is a computer. a typical computer holds information in volitale RAM so needs a constant power source to maintain information in volatile RAM. on a computer mother board this power source is a CMOS battery so if your computer loses time and date or other critical information in the BIOS resets that is because of a bad CMOS battery.
i have no clue if this is how it works for an ECM, but i would wager it does and i would say it's definitely possible for the ECM to lose memory and critical setup information if the info in volitale RAM gets reset because it loses its power trickle.
Last edited by babalu; Jul 25, 2010 at 04:58 PM.
sounds to me like it was hot..But it should have chilled out during lunch?I just stopped for gas the other day,shut down,pumped my gas and started the bike..It was idling faster than normal,but I just kept driving and no problems since..outside temp was over 100 so I just chalk it up to the heat..Fuel injected with all this ECM stuff just does weird **** sometimes..
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Joined: Mar 2007
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From: TOAK western branch
Sounds like an over full fuel tank or a bad TPS sensor. Does it want to die when you come to a stop after getting off the freeway or at a high speed. When you start her up cold does it idle way to high?
Seasoned HDF Member
Joined: Mar 2007
Posts: 66,948
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From: TOAK western branch
28 bucks for a tps sensor. It fixed mine and didnt set me back much for what its worth.
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Joined: Mar 2007
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From: British Columbia
sounds to me like it was hot..But it should have chilled out during lunch?I just stopped for gas the other day,shut down,pumped my gas and started the bike..It was idling faster than normal,but I just kept driving and no problems since..outside temp was over 100 so I just chalk it up to the heat..Fuel injected with all this ECM stuff just does weird **** sometimes..
the last year and a bit I've noticed I'm only getting about 190 to 240 kms per tank (118 to 150 miles).
The only thing that has changed on my part is I ride alot slower than I used to....but I would have thought I'd get better mileage going slower not worse.
I can only surmise that it's something to do with the EFI...but no one seems to know what the deal is.
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Road Warrior
Joined: Nov 2009
Posts: 1,635
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From: 501
My local Mech who jus recently completed the Factory sponsored Dyno school told me that more people were going to have problems with their factory ECM due to all the piggy back units on the market. Not that they didn't work, but they were going to cause problems with the factory module.
TPS sensor replacement is a good cheap start to a fix
That's all I have to offer!
and My $0.02
aka Bob
TPS sensor replacement is a good cheap start to a fix
That's all I have to offer!
and My $0.02
aka Bob
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Joined: Aug 2009
Posts: 96
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From: Delaware, OH
Normal computer memory is volatile, it'll get wiped every time you turn your computer off.
ECMs use a type of flash memory like EEPROM (Electrically Eraseable Programmable Read-Only Memory). It's non-volatile and it is flashable with a computer like a SERT.
Otherwise, you could hook up your fuelpak and reprogram the ECM right there on the bike. Or, if you ripped out your battery your ECM would take a dump.
ECMs use a type of flash memory like EEPROM (Electrically Eraseable Programmable Read-Only Memory). It's non-volatile and it is flashable with a computer like a SERT.
Otherwise, you could hook up your fuelpak and reprogram the ECM right there on the bike. Or, if you ripped out your battery your ECM would take a dump.