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Hi ausias
I bought a Lupo 1.2TDI 3L, a PD engine, and I'm trying to fine tune it to have the lowest consumption possible
I'm now messing with the torsion values, and would like to know if you can tell me more of your experience in this subject
First of all, I've found that the torsion values given by an European PD model, or an American PD model are oposite. That is, when you retard the ignition on a European model, the torsion values go positive, whereas in a US model the values go negative. And when you advance the ignition on a European model, the torsion values go negative whereas in a US model the values go positive
What I've also found is that the values displayed by VCDS in consumption change a lot when messing with it
With a torsion value of +4 (retarded) the consumption at idle shows an injection of about 3.6mg/st, 0.3l/h. With a torsion value of -4(advanced) the consumption at idle shows an injection of about 6.0mg/st, 0.6l/h
Now, this makes little sense to me, because theoreticly, with the ignition advanced, the the car would need less fuel for the same power, and the ECU is supposedly adding it. Also with the ignition retarded, the the car would theoreticly need more fuel for the same power, and the ECU is supposedly cutting it
With the ignition retarded, there is a noticeable loss of power at low RPM, and with it at 0 or slightly advanced, there is certainly more torque at low revs
I still haven't done full tanks to accurately measure it, so I would like to know, from your experience, if torsion values in TDI PD's really can change fuel consumption, or if this is only messing with the MFD?
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