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Ok! people always talk about reseting the ECU when changing anything on the car so that the car can re-learn to maximise performance/gain better fuel economy etc. the quote i hear over and over again is after all residual energy is drained from the car and you reconnect the battery you need to "thrash it!" i was wondering what most people consider "thrashing it". and if you have already done this then what revs were you thrashing it out to and for how long?

I recently changed my o2 sensor and drove it for a good 20mins reving each gear out to 5-6G's.didnt use 5th, was cruising through the local suburbs. Is this the way to do it. I figure that this will be telling the ECU that this is the driving style of the car and change the fuel/air ratio accordingly to a richish mix. Therefore im not expecting big savings on my fuel bill. What has everyone else done?

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Full load is all it needs. The more times it get's there, the finer it can tune itself. It constantly learns and recurves it's figures...it's just more coarse when you do the reset.

Full load means full boost, full throttle....you will probably need to take it to 6...no further. Do this in 1st, 2nd, 3rd, 4th (on highway), then resume normal driving.

Cheers for that. I did take 1st-4th to roughly 5/6G's. the car has always been a realy smooth ride and that hasnt changed. have noticed a increase in fuel economy aswell. roughly an extra 100km to a tank. pretty pleased with that.

Sorry to butt in on the thread... But i just want to confirm how to reset the ecu....

I read somewhere, all that is required is that you disconnect the Batt and stomp on the break a few times, reconnect the batt and do the above....

That sounds to simple..... was someone having a lend of me? hehe

Cheers,

Steve.

Sorry to butt in on the thread... But i just want to confirm how to reset the ecu....

I read somewhere, all that is required is that you disconnect the Batt and stomp on the break a few times, reconnect the batt and do the above....

That sounds to simple..... was someone having a lend of me? hehe

Cheers,

Steve.

Yes, that is correct. Dunno if it will make a difference but don't stomp on the brake, just keep your foot on it for 1 minute.

There are other ways but that is the most straight forward.

Whats it learning when you drive with the motor fully loaded?

Has it got a dyno strapped to the wheels and says, lets make some more power. this guy is up it, lets add an extra 10deg timing.

lol

The ecu might be able to learn basic crap like, closed loop fuel injection pulse widths and a target/estimated aac idle control valve values for idle jugement etc.

Knock sensing is going to be preety active, and just add the timing back in gradually (if not at every ign key off) If it pulls it out its for a reason.

Either way thats stating what it may be able to learn in the best possible case scenario.

Im still unsure of what flogging it makes it learn, the only time it can get feedback is in closed loop, light cruise driving from the O2 sensor, and it can check target idle speed to actual idle speed from the CAS.

It can't learn that you want it to make an extra 100hp at the wheels.

Whats it learning when you drive with the motor fully loaded?

Has it got a dyno strapped to the wheels and says, lets make some more power. this guy is up it, lets add an extra 10deg timing.

lol

The ecu might be able to learn basic crap like, closed loop fuel injection pulse widths and a target/estimated aac idle control valve values for idle jugement etc.

Knock sensing is going to be preety active, and just add the timing back in gradually (if not at every ign key off) If it pulls it out its for a reason.

Either way thats stating what it may be able to learn in the best possible case scenario.

Im still unsure of what flogging it makes it learn, the only time it can get feedback is in closed loop, light cruise driving from the O2 sensor, and it can check target idle speed to actual idle speed from the CAS.

It can't learn that you want it to make an extra 100hp at the wheels.

It does all of the above and more!

When I reset the ECU and give it a floggin, these rollers come out the side of the car and flip around in front of the back wheels. It then displays a hp figure (speedo needle). I can then use the clock adjuster to dial in the horsepower figure I want. It does one more dyno run then sets it all up for the added power.

How about NO! you freaky dutch bastard.

Hey there

Just want to know if the stock computer is capable of finetuning fuel/air mixtures till the engine is actualli running stoich (not rich not lean) when my r32 was stock it blew out black smoke =running rich.. now ever since i serviced it (oil+filter, spark plugs ) and added a 3"cat back exhaust and resetting the ecu, there is no black smoke coming out of the exhaust. i am pretty sure it not leanning out because i cant hear it ping (still on stock boost). just a bit puzzled why every other skyline i see with my mods blows out black smoke and mine doesnt, not one bit!

also because it not running really rich, hard driving sessions bring out glowing red manifold!

Edited by J_R32

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