Weird spark drop

[samh_08]

I was doing another AutoVE pass and I was noticing a jerk when I was basically idling back to my house. I looked through the log and noticed that my spark was dropping off to 0 for a second, then jumping right back up to where it was. No other data that I was logging gave me a hint as to what was causing it.

I attached a screenshot of where it was happening and my tune and log for the hell of it. Let me know what you think.

Thanks,
Sam

[samh_08]

Am I the only one who has had this? :hihi:

[WeathermanShawn]

When your spark drops are you dropping into Idle mode? (B0107 & B0108)

Based on the RPM's and how your MAP dramatically increases, does the car feel like it is about to stall?

I would look at B5934, B5935, & B5936 as your culprit. B5935 pulls up to 35 degrees of spark if your RPM's are above your desired Idle Speed.

[samh_08]

B0107 & B0108 are both set at 1 so I dont see how it would be transitioning.

The car doesnt feel like it wants to stall at all, its just an annoying jerk..

[WeathermanShawn]

I mentioned stalling as your log has that look. MAP rises, cylinder air jumps up, etc..

Nothing unusual like your AC kicking on? Noticed you higher IAT's. Spark loss can occur when the AC kicks on.

Other than something mechanical or accessory load, I can not imagine what would cause that type of spark drop at low speed/Rpm, especially in idle mode.