NefMoto

Hello All.

I am trying to tune my car but I am facing a issue where the car runs on a "diagnostic problem" or a Torque Intervention that I could not address.

The car is a S4 with a 2.7T. All the bells and whistles with Tial 770, EV14 1000cc @ 4,5bar and E100 (E98*) as fuel.

The issue is, running up to 30 psi (with the boost on the ME7 pegged) and the Load is around 200, no matter what the MAF scale. (I underscore KRTE to balance). If I rise the boost to 32 or over, the load is a bit higher, like 205 and then WGDC go to 10% and the car loses power.

I realised that the point where this happens depends on timing advance but is independent of MAF in Kg/hr (but maybe what is important is MAF Voltage?). I saw logs where loads are pegged at 191 for the whole pull. How do I do that?

To give some examples:
RPM      MAF (Kg/hr)      Load      Boost      Timing   PULL
4327      1090      203,00      28      8,25   OK
4288      1014      205,39      32      10,50   PROBLEM
4494      1298      205,97      32      10,50   PROBLEM
4499      1109      202,00      28      9,00   ok
5401      1570      205,95      32      15,75   PROBLEM
5439      1338      201,29      28      17,25   ok
6060      1618      209,49      32      21,00   PROBLEM
6092      1466      205,57      28      21,00   ok

These RPM when there is an issue is where the WGDC drops to 10%.
The Requested boost is always 2559,99 and the actual boost 2543,55.
The intriguing part is that even calling the MAF back, like in the 4288rpm above, the load is higher than the good pulls and it does have intervention.

I thought there was only a table limiting maximum MAF values, but it seems like there is a table limiting Load per RPM. And I don't how it is calculated because I bought it was a function of Air Mass and Timing only.

I appreciate any help.

Thanks,
Mark

5120. Please reread the s4wiki again. Don't run this close to the load or pressure limit. Ever.

Thank you for your answer, but on S4wiki it says to scale back MAF, and it didn't make any difference.

Understood I should not touch MAP limit. Will try that.

However, my main question is, how do people tune to have a limit of load of 191? What are the sensors that are used to effectively calculate load?


thanks

You cannot run 30 psi on a stock ecu bin. As you mentioned/read there is an internal limit because 8 bit adress, which works out to ~2500 mbar, to get around it you need to do some asm stuff , which halves the resolution and effectively relieves the load limit too -  it has been covered in detail on the forum.  Load is calculated from many many things, you need to over the FR/s4 wiki in detail.