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RPM specific lean-out

Kristian G

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Hi Kristian,

can you please do another log of the issue happening, use PC logging at 40 Hz , and LOG ALL PARAMETERS and repost, I don't have all the parameters I wish to look at in the RAR log file you have loaded.

Can you also supply the PCL file.



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You should check timing through a run yes. Dont nessesarily think it got something to do with the problem , but i suspect you got some timing scatter happening there.

Dont see VTC settings in the PCL, nor any AIT correction settings. Maybe im looking at a different version of teh program? 4.10?

Well the fuel IS being dumped in there, the burn IS happening (no stumbeling), it IS going lean, and timing is ok (maybe!).

How much extra fuel would you need to dump in to actually correct the reading?

Could it be som e sort of charge reversion at just this point?

Do you feel anything in the car att all? How big is that HP and TQ gain really?

What kind of knock detection do you have on it?

Looking closely (got the log on my 55" screen) i see a dip in the dRPM rate at the area of this happening... Im thinking you really should check that timing now and make sure its stable.

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I'm thinking either manifold air flow oscillation or fuel pressure oscillation.

no fuel damper installed. Only FPR, it could be an issue.. but difficult to identify.

I'll do a proper full check towards ignition.

On the torque gain its difficult to say, not a lot, but it does increase,

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Yeah charge reversion might be the case.

The fuel is being dumped in there so it has to go somwhere.

But then again. If it goes back into the intake again the charge should go even richer on the next cycle. Or at least there should be a rich dip AFTER the problemarea when the fuel goes where it should. ( Im just speculating here as i have never had such a problem to handle myself. So just thinking out loud)

As it doesnt then maybe it actually gets blown out the exhaust because of to much overlap (?). Got access to a gas analyser? Could pick up a possibly high HC count.

Really waiting for Dave to chime in again as i know he have done his share of RB`s

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