Too lean in open driving

[Itsuki]

Hi,

I´m having a issue when the car goes in open loop. It´s goes too lean. In closed loop it´s close to 14.7 but when it goes to open, suddenly goes lean.

I added fuel step by step but doesn´t goes richer. Even with big values, but always remains the same.

I´m thinking that the fuel tables aren´t the fault.

The injectors are 750cc from RC. I changed in the setup. The fuel pump it´s a Walbro, but I didn´t change the fuel pressure.

The calibration I used to start tunning was the base calibration for MAP tunning for 750cc injectors. What could be wrong?

The setup it´s a 3" custom CAI, Rotrex SC, Toda HE, and 2.5"Custom Exhaust.

I´ve attached a datalog to explain what I´m saying.

Example: In the 2:28 You could see that the injector time doesn´t goes higher in Open Loop, but in the tables has a value of 11.000 aprox (too high!!).

Thanks.

[Spunkster]

Without the calibration it is impossible to see what might be happening.

[Itsuki]

Sorry, I forgot added the cal.

I started with the inital cal for 750cc map calibration that cames in the software. As in open loop was lean, I added fuel proportionally but was all the same result. At last, I increased the fuel to wacky values if anything changed.

I attach the last cal.

Regards.

[Spunkster]

Has this been tuned on the dyno?

[Itsuki]

No, in a closed road to adjust the fuel.

[Spunkster]

I would start by getting this properly tuned on the dyno.

[Itsuki]

Yes, I will go to the dyno for sure. But why that behaviour in open loop?

[Hondata]

Have you relocated the MAP sensor so that it can see boost?

Fuel trims of +33% are a sign that you need to tune before you drive the vehicle any more.

[Itsuki]

Yes, the Hondata 4 BAR MAP sensor it´s located at the plenum chamber after the SC. I added a boost gauge to ensure that the MAP reads ok (and so it does). Also I supressed the MAF sensor and put the IAT after the SC and IC too.

If you see the datalog, it´s mandatory to add fuel with that short trims values and the behaviour in Open Loop. But if you look the calibration that I uploaded, doesn´t seems the fuel values so high?

I think I´m missing the point. If I change the value of the injectors to 750cc, I used to think that the values of the fuel just rescaled itself to the new size. Or must be increased proportionally to the resize of the injector?

Thanks for the help.

[civicRSA]

That calibration is not good for a rotrex supercharger. With just a quick glimpse at it the injector latencies are off. Load indexes are not correct for a rotrex supercharger and fuel values are too low.