What does reseting your ECU do? Will it hurt my car if it was already done? I have intake, exhaust, and pullies should I do it? Is it a good idea to do in the first place?

I heard you do it by starting your car, unplugging the ECU and then letting it idle for 15 min. then you just plug it back in and your done. Is that right?

 

umm....your car cannot run without the ECU plugged in.....can someone please instruct this guy on how to do this before he is posting a wanted ad in the classifieds for a prelude ECU.

 

You only pretty much reset your ECU when you see a check engine light after installing some mod. You do it by simplying disconnecting the negative battery. If the check engine light comes back on then you have a problem. Other than that, resetting the ecu does nothing

 

You can also reset the ECU by pulling the clock fuse. If you do have a Check Engine light on, jump the ECU to see what code it throws and to find out exactly what is wrong.

 

you should reset the ecu everytime you do an engine mod such as intake, headers.
your ecu has a learning cycle where it knows how your car is running and stores this in its memory. in doing this your ecu adjusts to how your car is running. (somewhat simple explanation but you get the idea). well when you install the intake you throw the computer off in that already has a setting for how your engine was running. this is why you reset the ecu, so that it can "learn" that you now have more airflow.

anyway to reset the ecu you simply remove its power source for the memory. just disconnect the battery or remove the fuse (clock/radio in underhood fuse box). if you or your mechanic use safe working "procedures" when working on the car, the ecu is reset automatically. anytime you work in the engine compartment you should disconnect the battery




Modified by 93preludevtec at 9:57 PM 6/11/2003

 

after you reset it, you have to let the car idle for 5 minutes without touching the gas, so that the car can remap the air/fuel ratio

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by dvp95 &raquo;</TD></TR><TR><TD CLASS="quote">You only pretty much reset your ECU when you see a check engine light after installing some mod. Other than that, resetting the ecu does nothing</TD></TR></TABLE>
According to what I have always read on several different boards covering many different cars that is totally wrong dude.
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote &raquo;</TD></TR><TR><TD CLASS="quote">you should reset the ecu everytime you do an engine mod such as intake, headers. you should reset the ecu so that it can see and "learn" the new mod</TD></TR></TABLE>
Bingo, that's what I was always told. I never did a dyno to see if there was a difference, but I figured that it couldn't hurt.

 

Resetting the ECU can be beneficial in OBD2 cars with mods. OBD2 ECU's will actually try to remove the benefits of mods like i/h/e Some people actually make their ecu have no memory so it will never really learn anything.

 

Sephro hit it on the head. All OBD2 cars will need to have their ecu reset every week or two so that their mods will not be detuned by the ecu. Any mod that changes air flow ect. will be detuned after it has time to complete its cycle. People get around this by doing the OBD2 workaround that can be found on ntpog.org. This resets the ecu everytime you start the car so the ecu will never detune your car.

 

question:

besides removing and replacing your nagative battery terminal, how else can you safely reset your ecu's memory, IE-pulling a fuse of some sort? Kinda like I used to do with older civics?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by CleanLIttleLude &raquo;</TD></TR><TR><TD CLASS="quote">What does reseting your ECU do? Will it hurt my car if it was already done? I have intake, exhaust, and pullies should I do it? Is it a good idea to do in the first place?

I heard you do it by starting your car, unplugging the ECU and then letting it idle for 15 min. then you just plug it back in and your done. Is that right?</TD></TR></TABLE>

turn your car OFF. Remove the clock radio fuse. Let car sit for 10-15 minutes. Replace clock radio fuse. Turn on car.

You'll notice the car start to lag in 900 or so miles. That is the amount of time it takes the ecu to DETUNE your car.