02 oscillation how to fix

[markvwguy]

I am trying to figure out how to remove the 02 oscillation I see in Tune Studio and Mega Log viewer. I have the 02 sensor scaled correctly with the custom linear WB setting. My old fluke 45 shows a steady signal to 4 decimal places to the ECU. I have not tried an VOM or set it up on a scope yet to see if those show the oscillation.

The AFR shows correct in TS, but the front bank voltage is about a volt off(both oscillate) . I have been correcting AFR scaling in the custom linear wideband it is finally is correct( centered in the oscillation), but the oscillation is there. The attachments are engine off just TS and LM1 powered.

My last struggle was solved by the advice and knowledge from the forum members thank you so very much!!


MS1 v3.0 board
LM1 innovate
direct drive wasted spark
36-1
The cam is turbo friendly
CB performance 2236 with 1.25 ratio rockers.
8.5:1 comp ratio
76mm stroke crank
1956cc aircooled T1

[Matt Cramer]

Where are the MS1 and the LM1 grounded?

[markvwguy]

The MS is grounded with four wires,pins16,17,18,19(DB37) twisted pairs at the engine block.
The LM1 is also grounded to the same ring terminal as the MS at the engine block as a separate singular wire. I have two LM1s and they both react the same.
I do have the power ground and the analog out 1&2 shield tied together via molex plug. No difference if the analog shield floats( not grounded with pwr gnd).

The engine has now 200mi on it. I'm trying to work out a detonation problem. Also, I have been out of Megasquirt tuning for about 4 years. I'm trying to start with the basics not jumping too far ahead.

My apologies I just posted a current tune from Sunday 7/25/16 while working with VEAL. I did not log the drive. I will post a Data log as soon as I can my next drive.

Thanks,
Mark

[whittlebeast]

Andy