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Webinar 233 - Transient Fuel - Lean Spikes

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Good Evening,

I am tuning an EJ257 with Cobb, and I have adjusted the tip-in enrichment to where the throttle response seems pretty crisp. However, rather than getting a lean hump in the data log, I am seeing sharp lean spikes, similar to what a misfire might look like. If the car feels good, should I be concerned about this? I thought initially that the engine was running too rich, but it AFR's right before the spike don't seem to indicate that.

Hi Costas is it possible for you to share your logging and maybe the map

I have the data log attached. I have the Wideband o2 logged under "Sensor Input Monitor Only TGV Right".

Attached Files

Hi Costas, I've had a look at the log you attached and I would not be worried about the lean spikes you're seeing. this sort of behaviour is completely typical and as long as the actual engine response is crisp I'd be happy.

Good Evening,

Thank you, I appreciate you taking a look.

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