Resetting ECU after mods
01-17-2005, 05:07 AM
#7
Supporting Maxima.org Member
Join Date: Jul 2004
Posts: 599
Pull the negative battery lead and wait 5 mins. Then put it back on. This should put the car back in to a "learn" mode for the first ~20 min of opperation. And there's also this way.
I thought about this some more and have to ask why do you need to reset the ecm? Is the SES light on? Any way use this process at your own risk!
1.Start engine and warm it up to normal operating temperature.
2. Turn ignition switch OFF and wait at least 10 seconds.
3. Confirm that accelerator pedal is fully released, turn ignition switch ON and wait 3 seconds.
4. Repeat the following procedure quickly five times within 5 seconds.
---Fully depress the accelerator pedal.
---Fully release the accelerator pedal.
5. Wait 7 seconds, fully depress the accelerator pedal and keep it for approx. 20 seconds until the MIL stops
blinking and turned ON.
6. Fully release the accelerator pedal within 3 seconds after the MIL turned ON.
7. Start engine and let it idle.
8. Wait 20 seconds.
9.Rev up the engine two or three times and make sure that idle speed and ignition timing are okay.
I thought about this some more and have to ask why do you need to reset the ecm? Is the SES light on? Any way use this process at your own risk!
1.Start engine and warm it up to normal operating temperature.
2. Turn ignition switch OFF and wait at least 10 seconds.
3. Confirm that accelerator pedal is fully released, turn ignition switch ON and wait 3 seconds.
4. Repeat the following procedure quickly five times within 5 seconds.
---Fully depress the accelerator pedal.
---Fully release the accelerator pedal.
5. Wait 7 seconds, fully depress the accelerator pedal and keep it for approx. 20 seconds until the MIL stops
blinking and turned ON.
6. Fully release the accelerator pedal within 3 seconds after the MIL turned ON.
7. Start engine and let it idle.
8. Wait 20 seconds.
9.Rev up the engine two or three times and make sure that idle speed and ignition timing are okay.
01-17-2005, 12:08 PM
#11
im still yet to come to a conclusion for myself if this is fact or myth ? i would like to believe it is true and this is speaking from the 4th gen information i have gathered. the a34 ecu could be different than the a32 ecu ?
many think that the ecu adjust to driving styles, mods, and octane rating. many maxima owners swear by it and many say its a load of crap.
Since I have little automotive knowledge I had the same nissan mechanic working on my car who has done every mod and all maintance. he swears up and down the ecu will adjust here are some examples:
(same car example)
granny drives to walmart and back then off to the pet store for bird seeds and doggie vitamins, young buck flys around town in the same model max ,stomping the gas, and pushing the car to the limits. if these two cars were to meet up and race, because the ecu learns the driving habits of each driver, the young gun in his maxima would win the race ( all things same ) just because the ecu has learned how the heavy footed maniac drives around.
i use to experiment with race fuel just some 100 octane. i told my mechanic and he says he man, the ecu has to adjust to the fuel, your wasting money. put the stuff in way ahead of time.
with mods, he also says the ecu will adjust to the mods, run the car and you will see
again im willing to say this sounds right, but here comes the big question. other guys have tested these theories out at the 1/4 mile strip and see no different in there times. this is done by taking 2 ecus and swapping them out, there is also dyno proof that even by swapping an ecu that has been in the car for a period of time, and then putting in an extra ecu, there is no difference.
so again, im lost.... im still leaning towards the ecu learns but with all the post and info on the boards and elsewhere it may be wishful thinking.
edit: sorry about the spelling, i must be drunk and not know it ?
many think that the ecu adjust to driving styles, mods, and octane rating. many maxima owners swear by it and many say its a load of crap.
Since I have little automotive knowledge I had the same nissan mechanic working on my car who has done every mod and all maintance. he swears up and down the ecu will adjust here are some examples:
(same car example)
granny drives to walmart and back then off to the pet store for bird seeds and doggie vitamins, young buck flys around town in the same model max ,stomping the gas, and pushing the car to the limits. if these two cars were to meet up and race, because the ecu learns the driving habits of each driver, the young gun in his maxima would win the race ( all things same ) just because the ecu has learned how the heavy footed maniac drives around.
i use to experiment with race fuel just some 100 octane. i told my mechanic and he says he man, the ecu has to adjust to the fuel, your wasting money. put the stuff in way ahead of time.
with mods, he also says the ecu will adjust to the mods, run the car and you will see
again im willing to say this sounds right, but here comes the big question. other guys have tested these theories out at the 1/4 mile strip and see no different in there times. this is done by taking 2 ecus and swapping them out, there is also dyno proof that even by swapping an ecu that has been in the car for a period of time, and then putting in an extra ecu, there is no difference.
so again, im lost.... im still leaning towards the ecu learns but with all the post and info on the boards and elsewhere it may be wishful thinking.
edit: sorry about the spelling, i must be drunk and not know it ?
01-17-2005, 04:13 PM
#12
Supporting Maxima.org Member
Join Date: Jul 2004
Posts: 599
When you swap an ecu you have removed power from it. My understanding is that it will loose the stored data from your driving habbits and thus needs to relearn it. Now if you changed the lookup table values that's a different story. You might be running a tweaked ECM intended for mods on a specific car. When you swap that to a differently modded car of course it will run different. Just my thoughts. I know that after I got my new battery installed my maxima seems more sluggish.
01-18-2005, 06:42 PM
#14
Senior Member
Join Date: Jun 2004
Posts: 951
Originally Posted by Glude
Some say it is. I dunno because I have never done it. I believe it has something to do with the ecu being obd2. Before 95 it was obd1 and cars would adjust to mods.
02-18-2005, 06:56 PM
#15
Donating Maxima.org Member
Join Date: Jun 2003
Posts: 27
[QUOTE=Ceasars Chariot other guys have tested these theories out at the 1/4 mile strip and see no different in there times. this is done by taking 2 ecus and swapping them out, there is also dyno proof that even by swapping an ecu that has been in the car for a period of time, and then putting in an extra ecu, there is no difference.
so again, im lost.... im still leaning towards the ecu learns but with all the post and info on the boards and elsewhere it may be wishful thinking.
edit: sorry about the spelling, i must be drunk and not know it ?[/QUOTE]
I may be wrong but going from my experience from my Grand Prix GTP which also was OBD2. Simply swapping the ecu's alone most likely won't improve performance and may also hinder it. See the ecu has a crankshaft position sensor which it relies on to achieve the proper timing. changing the ecu will throw off the accuracy of the crankshaft position sensor, thus throwing off your timing. An example of what i'm talking about would be to take off a distributor ignition, crank the engine and simply put the distributor back in. The timing would be all out of whack. It could be advanced of retarded in the end result. After removing the ecu and replacing it with a different one you would need to get a "case learn" ( as it's called on GM cars) to relearn the crankshaft position. Keep in mind this won't be an issue if you remove the ecu and put it back in say if you sent your ecu to get reprogrammed, without starting the car. Maybe someone with more insight into this particular unit can shed some more light on this as i'm not familiar with this unit, i'm just going by the way the americans did things.
so again, im lost.... im still leaning towards the ecu learns but with all the post and info on the boards and elsewhere it may be wishful thinking.
edit: sorry about the spelling, i must be drunk and not know it ?[/QUOTE]
I may be wrong but going from my experience from my Grand Prix GTP which also was OBD2. Simply swapping the ecu's alone most likely won't improve performance and may also hinder it. See the ecu has a crankshaft position sensor which it relies on to achieve the proper timing. changing the ecu will throw off the accuracy of the crankshaft position sensor, thus throwing off your timing. An example of what i'm talking about would be to take off a distributor ignition, crank the engine and simply put the distributor back in. The timing would be all out of whack. It could be advanced of retarded in the end result. After removing the ecu and replacing it with a different one you would need to get a "case learn" ( as it's called on GM cars) to relearn the crankshaft position. Keep in mind this won't be an issue if you remove the ecu and put it back in say if you sent your ecu to get reprogrammed, without starting the car. Maybe someone with more insight into this particular unit can shed some more light on this as i'm not familiar with this unit, i'm just going by the way the americans did things.
06-22-2005, 03:23 PM
#18
Senior Member
Join Date: Jan 2005
Posts: 203
The ECU is ALWAYS learning... it adjust timing, fuel, etc... according to all the variables that are sent to the ecu from all the sensors.
If you have a CEL, try disconnecting the terminal and stepping on the brake pedal and turning the key to the start position. It has worked for me.
If you have a CEL, try disconnecting the terminal and stepping on the brake pedal and turning the key to the start position. It has worked for me.
05-19-2011, 01:15 PM
#20
Pull the negative battery lead and wait 5 mins. Then put it back on. This should put the car back in to a "learn" mode for the first ~20 min of opperation. And there's also this way.
I thought about this some more and have to ask why do you need to reset the ecm? Is the SES light on? Any way use this process at your own risk!
1.Start engine and warm it up to normal operating temperature.
2. Turn ignition switch OFF and wait at least 10 seconds.
3. Confirm that accelerator pedal is fully released, turn ignition switch ON (without running the motor of course) and wait 3 seconds.
4. Repeat the following procedure quickly five times within 5 seconds.
---Fully depress the accelerator pedal.
---Fully release the accelerator pedal.
5. Wait 7 seconds, fully depress the accelerator pedal and keep it for approx. 20 seconds until the MIL blinks.
blinking and turned ON.
6. Fully release the accelerator pedal within 3 seconds after the MIL blinks.
7. Remove key then turn to first position again and wait 3 secs then start engine.
7. Start engine and let it idle.
8. Wait 20 seconds.
9.Rev up the engine two or three times and make sure that idle speed and ignition timing are okay.
I thought about this some more and have to ask why do you need to reset the ecm? Is the SES light on? Any way use this process at your own risk!
1.Start engine and warm it up to normal operating temperature.
2. Turn ignition switch OFF and wait at least 10 seconds.
3. Confirm that accelerator pedal is fully released, turn ignition switch ON (without running the motor of course) and wait 3 seconds.
4. Repeat the following procedure quickly five times within 5 seconds.
---Fully depress the accelerator pedal.
---Fully release the accelerator pedal.
5. Wait 7 seconds, fully depress the accelerator pedal and keep it for approx. 20 seconds until the MIL blinks.
blinking and turned ON.
6. Fully release the accelerator pedal within 3 seconds after the MIL blinks.
7. Remove key then turn to first position again and wait 3 secs then start engine.
7. Start engine and let it idle.
8. Wait 20 seconds.
9.Rev up the engine two or three times and make sure that idle speed and ignition timing are okay.
BTW - When you press and release the accelerator pedal you can do it at a fair pace...and count while you do it to help you....1,2,3,4, 5. then count one one thousand, two one thousand, three one thousand, four one thousand..until you reach seven...then fully press the accelerator pedal (for about 20 seconds) until you see the SEL light blinking. Then wait three seconds and remove your foot...and key from ignition. And follow the rest of the instructions....
Once you get the knack of it you can do this with your eyes closed in under two minutes of getting in to your car. I do this every time I do fill-up. In winter I use low grade gas...sometimes mid grade...however in the summer I use the highest grade gas available. In Canada we have Petro-Canada that has 94 octane...after I do ECU reset that 94 Octane feels like rocket fuel! Of course , I have a lot of mods too which does help! Very easy to do once you get the feel of it.
Last edited by xorbitman; 05-19-2011 at 01:21 PM.
05-20-2011, 06:49 AM
#25
05-20-2011, 08:35 AM
#26
"After reset...check ignition timing."
Too funny, what diagnostic software and laptop OBDII to Serial port cable should we use?? This may be like the people who taste wine for a living, there are those who can tell if the timing is correct by revving the engine in neutral.
Too funny, what diagnostic software and laptop OBDII to Serial port cable should we use?? This may be like the people who taste wine for a living, there are those who can tell if the timing is correct by revving the engine in neutral.
05-20-2011, 05:55 PM
#28
what I figured. Only ever seen it useful to clear a code or CEL, and if it returns you have a problem.
but now since the car is always learning and adapting... would resetting erase all that for whatever reason and start like from factory? maybe if you change owners?
but now since the car is always learning and adapting... would resetting erase all that for whatever reason and start like from factory? maybe if you change owners?
05-20-2011, 06:16 PM
#29
Interesting news: There are now a few different companies out there that sell moded ECU software that can reprogram your ECU! Some as inexpensive as under $300! Of course you should have this done by a qualified shop/tech and you should have a baseline dyno then you can reprogram the ECU then Dyno run again then finetuning of the results. This is similar to what Technosquare was doing except better and way less expensive and/or risky.
06-22-2012, 09:16 PM
#30
Hi, sorry to bump this. I currently have a low idle issue where it idles below 500 and does not stall. I tried brake pedal relearn process and no success. Is this the only way to adjust idle? I have a NISMO CAI and a Vias plate.
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