Resetting the ECU

[Anthony38]

Quite awhile back I read on this forum, someone metioned the resetting the ecu will retain my fuel consumption back to normal. Is this true?
Cause at the moment my EM1 is only able to clock up to 410kms per tank.

Can someone fill me on how to reset my ecu?

thanks in advance

[ECU-MAN]

disconnect the battery for 30 seconds

[Anthony38]

both the negative and positive terminals?

[ECU-MAN]

just positive

[Kit]

I don't think resetting the [acronym:c593c17502="Engine Control Unit"]ECU[/acronym:c593c17502] will aid your fuel economy. However, if you had just made some breathing mods you can reset it so it "recalculates" mixtures.

the way to do it is:
- warm the car up to its normal operating temperature
- turn the car off
- remove the following fuses in the fuse box: ECM and hazard (I am pretty sure that hazard is the second fuse that needs to be pulled, however its been a couple of years since i last did it so I can't be 100% sure)
- leave disconnected for 1 minute
- reconnect fuses
- make sure no electricals are turned on (that is, air con, radio, demister etc)
- turn on the car WITHOUT stepping on the accelerator
- let the car run for a few minutes
- turn the car off (this must be done)

your [acronym:c593c17502="Engine Control Unit"]ECU[/acronym:c593c17502] will be reset now.

[SiR]

my EM1 is only able to clock up to 410kms per tank.


But that sounds about right to me. 410kms from a 45L tank (I'm assuming you mostly do city driving with the occasional hwy. run) sounds very reasonable imo.

[Kit]

i used to get about 520 out of a tank of fuel on my ek4, and that was a combination of city/freeway, but mainly city

[Anthony38]

i was looking at the fuse box and I could find the fuse for the [acronym:47ae754b6c="Engine Control Unit"]ECU[/acronym:47ae754b6c]. I manage to find the "hazard" fuse.

Can you tell where I can locate the [acronym:47ae754b6c="Engine Control Unit"]ECU[/acronym:47ae754b6c] fuse?

[SiR]

i used to get about 520 out of a tank of fuel on my ek4, and that was a combination of city/freeway, but mainly city

Holy...!! That much?! Did you not [acronym:30dc35b431="Valve Timing and lift Electronic Control"]VTEC[/acronym:30dc35b431] at all? :lol:

I usually only get around 330km's with maybe 10 litres of petrol still left in the tank.

Maybe I should reset my [acronym:30dc35b431="Engine Control Unit"]ECU[/acronym:30dc35b431] as well and see if things improve?

Btw, Anthony, sorry for hi-jacking your thread a little. :)

[gelo]

520?!
that is alot!

i usually fuel up at 400km
where the indicator is at E but the light hasnt come on
i usually have like 6-7 litres left
this is without opening vtec at all(ok...maybe once or twice.....)

[Kit]

520 was with occasional vtec..
but bear in mind, i was totally anal about the maintenance of my car...
I used to run Mobil 1 10W30 (gold label) oil, changed every 5000km, and i used to run castrol syntrax gearbox oil changed every 10,000km. and always run BP Ultimate

[SiR]

520 was with occasional vtec..
but bear in mind, i was totally anal about the maintenance of my car...
I used to run Mobil 1 10W30 (gold label) oil, changed every 5000km, and i used to run castrol syntrax gearbox oil changed every 10,000km. and always run BP Ultimate

Same here Kit - I'm very anal about the maintenance of my car too. HPEO, changed every 5000km (I normally change before the 5k km mark, usually 49xx kms or thereabouts) and always run BP ultimate as well. Plus I don't drive my car much either.

[Kit]

what is HPEO? do you mean Honda FEO oil? that stuff isnt very good.

also whats your ignition timing like? running stock (honda factory servicing) timing?

[luzinit]

that is VERY good economy Kit. In my EK4, the most i've managed out of a tank was 440ish kms, and that was running with the fuel light on for quite a while!
I am also very anal about the maintenance of my car, however I used honda FEO, and AFAIK ignition timing is stock. Also, I have recently got a catback and hiflow panel filter, do you think I would need to reset the [acronym:52b2c7733b="Engine Control Unit"]ECU[/acronym:52b2c7733b] so that it 'recalculates' mixtures?

[h22a accord]

luzinit, yes, now is the time to reset your ecu.

[ATSE]

Man does resetting the [acronym:5e49931849="Engine Control Unit"]ECU[/acronym:5e49931849] do anything anyway? I mean... once modifications are done... the [acronym:5e49931849="Engine Control Unit"]ECU[/acronym:5e49931849] will self adjust to the new mods anyway won't they? I did it once when I bought my EK and it didn't make any difference at all... the only use of it is to clear CEL's once a problem is fixed.

[SiR]

what is HPEO? do you mean Honda FEO oil? that stuff isnt very good.

also whats your ignition timing like? running stock (honda factory servicing) timing?


Yeah, typo...my bad.

I used to be using Honda FEO all along, so unless Robert (Hanny's) has changed it to something else, then it should be the same.
Yep, factory ignition timing, unless Robert played around with it during my last service.

[h22a accord]

Man does resetting the [acronym:c917a503c2="Engine Control Unit"]ECU[/acronym:c917a503c2] do anything anyway? I mean... once modifications are done... the [acronym:c917a503c2="Engine Control Unit"]ECU[/acronym:c917a503c2] will self adjust to the new mods anyway won't they? I did it once when I bought my EK and it didn't make any difference at all... the only use of it is to clear CEL's once a problem is fixed.



yes the engine will self adjust but it will take time.

pull the fuse and it will do it straight away.