Idle afr jump and lean cruise surging

[Jason W]

Hi.

I am yet to upload my log and tune as I have attempted it this morning and nothing shows up to attached after uploading! I will try again after work...

After playing around with the tune on my new engine for the last few months, I am fairly happy with most of the tune (I still need to get to a dyno, or buy a wideband for proper PE adjustment though) except I can't seem to lock down a nice way to do my idle AFR or lean cruise mode.

In my current tune, my idle is OK when I am actually at idle (it shakes a little, but it may be that I am commanding too low an RPM for this cam). My problem is that when gently accelerating off idle the PE mode starts kicking in and out up to around 1200-1500 RPM. I have PE mode set in the 400 and 800 RPM cells to come in at 0% throttle, and a commanded AFR of around 13:1. Once I get anywhere between about 900-1200 RPM it seems to surge as the AFR is jumping between 13:1 and stoich.

As for the lean cruise, I am finding this frustrating as I ended up setting it to come in when I am cruising around town (around 60Km/H) and when it cuts in my afr jumps all over the place to the point of feeling the car surging and leaning off.

I have also been playing with EOIT, but I haven't noticed too much of a difference from my initial increase in timing, so I may end up reducing this a bit again... This did initially help a heap though with the short circuiting of fuel!

Thanks for any help any of you can give me.

Regards,

Jason.

[Jason W]

OK. I have finally been able to attach these files! Must be something in the coding of Google Chrome! Internet Explorer actually worked!

Anyway, the log attached shows a bit of the AFR pulsing I mentioned, but isn't a good log to show my off idle surging I was talking about I can actually feel the car getting more and less power though when idling with my foot on the brake, but the most annoying part is the wife feeling it surge when gently accelerating! I don't generally feel it, cause I usually accelerate quickly past that point!


23.08.2014.hpt15.08.2014 3.hpl