MicroSquirt.com read only forum (Jan.15,2018)

I'm running MSII V3.0 2.35 code with an LC-1 WB 02.I've got the car running pretty well under all conditions except for one aberation.In my logfile and also on the AFR meter in Megatune whenever I let up on the gas I get a very rich reading.I've reduced my decel fuel amount to 60% progressively thinking this was the problem but no change.It would appear that as MAP and PW are falling something is driving down my AFR?
Any suggestions ?I enclose a small piece of my log and my VE table and AE table.

Bump

The decel rich issue is pretty common. It happens for a number of reasons. It should not really affect drivability, though. The other issue I see is that your VE table appears to be a generated one and not actually tuned. I would not really start tuning these other things until I got the VE table a bit closer to reality.

Use VexME or AutoTune (in megatune) to start getting this table closer to what your engine needs.

Keith believe it or not my VE is the result of many hours and miles of tweeking and autotuning.My car seems to run very well with these values but given your observation it would seem that I'm missing something.Any clues ?

Look at the GEGO column of the log. It is constantly correcting by many %. Just as a cursory look, it does not have the telltale peaks and valleys as the VE changes due to exhaust scavenging and intake tuning.

KeithG

Posted by email.

Keith my EGO authority is set at 5% because I found that Autotune was making some apparently illogical changes and yes GEGO does appear to be correcting within this range.Is this undesirable ? .Because of the AFR diving to 9-10 for no apparent reason I figure that this is throwing off Autotune.What specifically about my VE table doesn't look right ?

MurrayA4,

Your VE table and settings look okay to me. However I would try setting the 'end pulsewidth' to 0.0 (from 0.2). The reason is that the end pulse width is larger than the lower accel bins, making the accel enrichment increase over the duration of 0.4 sec., which probably isn't helping.

You can also decrease the decel fuel amount some more, 60% is pretty conservative - some people are able to run 0% without problems!

Lance.

Dunno what to say. It just does not look right to me. Tuned maps I have looked at do not look that uniform. As for the GEGO, it never sits around 100. It is either 105 or 95 and does not seem to want to sit near 100 which would indicate a tuned map at in that range. Mine oscillates around 100 +/- 2% at constant speed and load and that is with MS-1.

My comments may be a red herring, though, do not take it as gospel. My experience is really only 1 car.

KeithG

I wish my VE looked that nice. Lucky. Soon though soon.

A.J.

Thanks Guys.Ok Lance I'll make the adjustments to AE as suggested.Keith I agree that my goal is to see GEGO making the smallest changes possible but I'm also starting to realize that may not be possible.I live in a hilly area and I've noticed that VE settings that are appropriate on flat ground may be quite different when travelling up or down a hill.The combinations of MAP/RPM and VE have to deal with a wide variety of loads so I guess I have to be satisfied if the VE number falls somewhere in the middle.