Megalogviewer Analysis Question

[rv3bpilot]

The upper part of the graph the white line is the RPM and the Green line is the throttle position sensor. Does anyone know if the RPM's and throttle position sensor suppose to be more smooth and not so jagged at this?



Robin
Megasquirt II
Pertronix electronic ignition used as a trigger for MS II
6 Cylinder Chevy Corvair
MS II controlling the ignition timing, Rev. limiter set at 3200, lower part of graph shows that works great.

[kjones6039]

The traces in the log certainly look a little suspicious, but I think it would be more helpful if you posted the actual log. Screen shots are generally a pain to try to analyze.

Ken

[rv3bpilot]

I don't know how to post the actual log. In fact it took me a while to figure out how to post this screen shot.
The white line in the upper part of the graph is the RPM and the Green jagged line is the throttle position sensor. This engine is in an airplane where the throttle movements are slow or steady.. You can clearly see when I changed the throttle setting, it spiked then went back to the normal jagged line.
I have the Throttle position sensor wires shielded along with the engine temp. and inlet air temp. I even shielded the wire from the coil all the way back to the MS II controller. I have been placing capacitors on all electric motors to eliminate noise.
But I have not yet put shielded wire on the distributor wires leading to the MS II...
Can some one put a actual log on here so I can look at it and compare it to mine..
Robin

[kholman]

To post the log, attach it to a message post as described here: viewtopic.php?f=39&t=34965

[trakkies]

Most usual cause of noise is incorrect grounding. The way to test is to unplug the MS, and check if any of the sensor grounds is still connected to ground,

[rv3bpilot]

Code: Select all

[IMG]http://i59.tinypic.com/2cdxtnp.png[/IMG]

This is a graph taken this morning. I seemed to have most of static taken out of everything but the motor RPM's
Can anyone tell me how to smoothen out the RPM graph..
Green is the engine RPM
Yellow MAP
Red Throttle sensor

MS 2
6 cylinder
port fuel injection
ignition timing run by MS 2
Protronix electronic ignition in distributor used for crank position and RPM trigger

[rv3bpilot]

I found the answer to my problem in the Megasquirt II manual. The hall sensor was not noisy but the power wire feeding the hall sensor was so I put a capacitor on that wire. Also I felt that since I could not avoid having the wires to the spark plug wires I replaced the distributor wires that go to the hall sensor with shielded wires. Here is a screen shot of the results. It worked great! The part where the lines go all the way to the top is where I was adjusting the acceleration table for a snappier response.