MSefi.com read only forum (Jan.15,2018)

If your Hall sensor is giving you a 0 or 12 v output when the sensor output pin is not connected to anything, then it has an internal pull-up arrangement. There is no general statement about 'correct' as to whether the voltage is high or low when the metal or window is present next to the sensor as ...

I did a little checking after I found the part # for the IAC driver chip. The UDN2916LB full bridge motor driver chip used on MS2 already has internal fly-back / recirculation diodes so no external fly-back diode is required.

I am configuring my MS to switch my radiator fan relay (ground switching mode) using IAC1. I am speculating that because the IAC outputs are rated to switch an idle air valve, that I do not need to use an interposing transistor to handle the relay coil current (about 35 mA). I am also speculating ...

I have been wanting to do a little more refining of the operation of the O2 sensor in closed loop operation on the Megasquirt II installation on my 1971 Volvo B20E. Right now, I am just using the proportional gain feedback loop with a gain of around 20% or 30%. Unless the operating conditions are ...

I have attached the log. The event in question occurs right around record 722 (57959 seconds).

I don't know whether this is a tuning / configuration issue or a software or firmware issue; but, I am going to start with tuning / configuration.

I was doing a datalog during a start and warm-up as part of tuning my start-up parameters. While scrolling through the datalog, I came across this ...

Thanks for the clarification.

I had corrected the number and it made no perceptible change to the operation of the engine. I am running MAP so that should be expected based upon your reply.

Yes and no. I recall seeing this information when I was doing my initial install a year + back; but, could never find it again. Thanks for the link. I had tried the F1 function; but, it just took me to the EFI Analytics resource page which didn't help much.

The discussion of the transport delay is ...

LT401Vette wrote:The settings in those dialogs are specific to what ever firmware you are using.
What firmware would that be?

MSII Rev 2.920

Interesting observation on the effect of reduced voltage at start up. I assume you are talking about the sensitivity of the injector offset (opening time) to battery voltage? If your voltage sensitivity was too large, then yes it would be increasing the offset more than it needed to which would ...

I am using version 2.6.19 of Tuner Studio with a MSII controller which is running batch fire fuel control. In the Fuel Set-up / General Settings menu, there are entries for Engine displacement, Injector Flow Rate and Injection Timing Delay. What are the Engine Displacement and Injector Flow Rate ...

I have been looking for documentation on the PID wideband controller algorithm, in particular a discussion of what the two transport delays are modeling. A breakdown of the control blocks for the PID / Smith Predictor would be interesting. I cannot find any documentation in the Mega manual. Where do ...

I never noticed the flags in Mega Log Viewer. I guess I was too occupied with the other stuff.

It may be academic now. The flag was re appearing consistently until yesterday. Since then it has gone out when the engine comes up to temperature and stayed off. I do have a bunch of logs that I ...

I was thinking about doing that; but, not clear which variables I should log. Should it be the Gwarm variable? I am not sure what the Gwarm variable is.

As a note, it is not apparent that any thing is happening in the controller / engine when the warm up flag on the dashboard turns back on. As far ...

Just recently, I noticed that after starting my car and letting it warm up, the indicator on the Tuner Studio dash indicating warm up enrichment would go off when the coolant temperature had exceeded the high value in the warm up enrichment table. However, after a couple of minutes, the indicator in ...

I decided to go and measure any potential offsets between the internal ground on the MS (pin 19) and the ground connection that I was using for my LC1. Connecting my scope between the two ground points and with the car idling, there is no measureable DC offset between the two points. The only thing ...

No criticism taken. B Sc in Electrical Engineering so I am well aware of the effect of offsets that can arise from ground loops.

The LC1 controller has two separate grounds, the heater and the system ground. Because of the large(r) DC currents and the potential for unnecessary DC offsets, the ...

Absolutely everything is grounded at a common point on the engine intake manifold - so no offsets.



The common signal ground point should be the MS.

What do you mean the MS is the grounding point? The megamanual is pretty clear that the various ground points on the MS 37 pin connector are ...

Absolutely everything is grounded at a common point on the engine intake manifold - so no offsets.

I fixed the problem. I used the custom wideband with linear curve in Tuner Studio with 0 volts - 7.35 AFR and 5 volts - 22.38 AFR. The dash gauge and the AFR display in Tuner Studio now read ...

Does anybody know what the voltage / lambda settings are if you use the default settings for the LC1 wideband controller in Tuner Studio? For some reason. The default set-up for the wideband output on the LC1 controller is 0 volts - lambda = 0.5 and 5 volts - lambda = 1.523. I am thinking that Tuner ...