tuning obd1 and obd2

[domantas]

what are the differences when tuning obd1 and obd2?

i heard that obd2's most of the time run on o2 sensor fedback and fight safc settings and need reset ECU after some time

What about obd1's? Does if fight safc settings in anyway?

[alanek]

did you already choose what to tune your car with ?

[domantas]

I will use Safc thats for sure, because IMO thats the best option if you go with stock 330 injector setup.

They say there are two modes how ECU delivers fuel. Closed loop at regular driving and open loop when at WOT and engines warm up.

Using stock obd1 karmen maf it will be able to adjust fuel acordingly and a/f ratio will be stoich but when you slam on gas and hit closed loop mode you can ritchen up fuel in order to be safe. I learned this in the other post. Guys helped me a lot and will see how that happens.

Tuning is very hard thing to learn but you know, I say if a person didnt learned how to fly it means he didnt wanted enough... I still dont know how ECU know when to go into closed loop. TPS sosition? If so where should I set my high-trotl % at my SAFC

[domantas]

Can anyone confirm that stock ECU will fight any changes made by safc while factory ECU is in closed loop? As far as I have heard that its in open loop when going WOT, but what WOT actualy means? TPS position, rpm or load?

Could I force my ECU to open loop just by disconnecting my o2 sensors? How that would affect my car?

Is this even a big deal while I will be using my stock injectors? Some people say ECU will adjust AF mixture to correct ratios without any AFC. Is that a true or myth? Of course I will have wideand handy

[domantas]

when obd1 ECU switches to open loop? Is it based on throttle, rpm, load, or even coolant temp?

[Sandra]

cia ne tas pats nu bet nzn maybe helpful :) :*:*
In closed loop operation the ECU uses one or more oxygen sensors as a feedback loop in order to adjust the fuel mixture. This gives the name ‘closed loop’ from the closed feedback loop. The ECU won’t run in a closed feedback loop all the time, so ‘open loop’ is used to describe the operation of the ECU when the mixture is not being adjusted in this way (usually when the engine is cold or when running under high load).

It is best to disable closed loop operation while tuning. Otherwise what commonly occurs is that the ECU will alter the mixture using the long term adjustment while the car is idling between dyno runs, which means that the mixture is not repeatable between dyno runs.

If changes are made to the engine which alter the amount of fuel that is delivered (bigger injectors, increased fuel pressure or altering the air temperature sensor voltage) the ECU will compensate the best it can using the long term adjustment. Under high load when the ECU stops running in closed loop the long term adjustment is still used so increasing fuel delivery via these means in not recommended unless the ECU is recalibrated or closed loop disabled.




OPEN LOOP - this is the mode your ECU is in until the coolant temperature and a couple other sensors get to operating values. This is also true when you are at WOT or when throwing codes/ CEL's

CLOSED LOOP - the ecu uses information primarily from the Oxygen Sensor and adjusts fuel delivery and timing to achieve minimum emmisions, better gas mileage and power.

[Sandra]

Thas what i found not sure if thats right ya know me
Well the WOT its box which adds two major features to any car. They are No-lift shifting and 2-step launch control.

The No-Lift Shift feature makes no-lift shifting easy by cutting your engine's ignition for a very short period while you no-lift shift. No-lift shifting is keeping the gas down through the shifft. The ignition cut allows the synchros in your transmission to mesh easily, reducing the chance of missing a gear and damaging your transmission. Keeping your foot down through the shift also allows you to hold boost through the shift, thereby significantly improving your E.T.

The major benefits are:


Lower ETs

Reduced chance of missing a gear

More consistent, effortless shifts

Reduced wear on the transmission

Reduced chance of major transmission damage

The 2-Step Launch Control modulates the ignition by cutting power to individual ignition coils to hold the RPM you want to launch at. The turbo will spool up while you do this. You can use this feature for a more consistent and more powerful launch in boost!

[Sandra]

Good Luck !!!! :)

[Sandra]

If you don't have the O2 sensors connected, it will force the ECU to go into a default open-loop mode. It will not affect power because it's in open-loop at full load anyway. It might affect fuel consumption, and it WILL affect emissions. There is no way to predict how good/bad the default open-loop programming is. Most cars run way rich when they don't get a good O2 sensor signal