Misc issues with MS2 v3 testing

[5.3LS10]

Hey everyone. I have had a few issues with my megasquirt assembly so far and just wanted to reach out and see if there are any troubleshooting tips you can help with. I have a MS2 running mxextra latest and greatest.

I noticed when testing my MS2 with the jim stim the O2 reading in tunerstudio is not fluent. Seems to jump around. I have the jumper on the jim stim for wideband and I have tunerstudio setup for wideband as well. I noticed this on the megastim as well. Are there any other settings I need to check or do I need to start looking at the component level and seeing if I installed something wrong or is it not supposed to be fluent?

Also I was reading the configuration instructions for LS motors.
http://www.msextra.com/doc/general/tach ... tml#vrpull
This seems to be telling me that "LS1" motors that utilize 24x cranks are VR and LS2 motors that have 58x crank are hall effect. I thought all LS engines were Hall effect? If this is the case even for a 5.3L with the 24x crank would I have to follow step 3 for the "LS2" hall effect setup?
"c) Install a 1k resistor (any value 470R - 2k2 is likely ok) in the proto area. Connect one end to the 5V hole and join the other end to VRIN with a jumper wire. "


Also looks like the jimstim firmware does not simulate the ls engines 36-1 pattern correctly? I have seen some posts that it is possible to customize but nothing in detail on how to actually do it. Could someone point me in the right direction?


Thanks
Shane

[DaveEFI]

The JimStim instructions show you how to set it for a 36-1 wheel. What you may have read is the waveform generated by the JimStim isn't quite the same as from a VR sensor - but is pretty close to what you'd get from a hall effect.

All this means in practice when using a VR sensor is you may need to adjust the VR input slightly between stim and actual sensor.

[5.3LS10]

I am going to post some more detail on the O2 issue. If I turn the O2 pot all the way to the left the tunerstudio reading is 14.80. As I turn it clockwise it will jump to 16.90 and and I keep turning clockwise it then goes to 12.10 until the pot maxes out. One other thing... while I adjust the O2 pot I see the Fuel load changing between the jumps that the O2 reading gives. Is this normal?

Also....

The JimStim instructions show you how to set it for a 36-1 wheel. What you may have read is the waveform generated by the JimStim isn't quite the same as from a VR sensor - but is pretty close to what you'd get from a hall effect.

All this means in practice when using a VR sensor is you may need to adjust the VR input slightly between stim and actual sensor.

So I have followed the instructions on the jbperf site. I have a jumper between "Pull Up" and "12v" on the primary and secondary inputs. I also have a jumper across the top and middle pin of the primary and secondary trigger and the #3 dip switch in the "on" position. From what I have seen this is the way to setup the jimstim 2.0.3 for the ls crank emulation.

I have also adjusted the pots according to the instructions.

Am I missing something?

[elutionsdesign]

I've noticed similar issues with the O2 readings on the stim in the past, they are usually due to something disrupting the 5V. Put a voltmeter on the signal itself and turn the knob, if the voltage is jumping around then the megasquirt is probably reading things correctly and the issue is your stim, if the voltage is not jumping around but the O2 value in Tuner Studio is then you've got to take a look at the circuit on the board.

[5.3LS10]

I've noticed similar issues with the O2 readings on the stim in the past, they are usually due to something disrupting the 5V. Put a voltmeter on the signal itself and turn the knob, if the voltage is jumping around then the megasquirt is probably reading things correctly and the issue is your stim, if the voltage is not jumping around but the O2 value in Tuner Studio is then you've got to take a look at the circuit on the board.

Thank you for that suggestion! I put a volt meter right on the pot and on the db37 O2 pin and the voltage readings seem rather linear to the POT adjustments so I will have to look into their being an issue on the megasquirt and not the stim. I will try to find the diagrams from the megamanual that have all the circuits drawn out so I can go from component to component and verify things.

Thanks again!

[5.3LS10]

Okay so I used this http://msextra.com/doc/general/ms2v3schems.html#p2 to trace out the circuit for the oxygen sensor. I verified connectivity from the O2 pot to the DB37 connector to R10 and R11 and C10 and finally to pin 28 of the ECU. I have the same voltage all the way there. I noticed no voltage drop across the R10 (1K) resistor. Shouldn't I have some voltage drop?

So basically my Voltage at the POT and pin 28 is the same. Is this normal?

[5.3LS10]

Also I have verified R10 is in fact a 1K and R11 is a 1M... or at least that is what the color bands are telling me.

[5.3LS10]

Another update I used a scope to trace back the crank signal from the jimstim to pin 14 on the ecu and I can see a square wave at the ECU. Does that mean that my tuner studio settings are wrong?

[billr]

Do you see just a square-wave with the scope, or is it the correct 36-1 pattern?
Oh, yeah...

[5.3LS10]

Do you see just a square-wave with the scope, or is it the correct 36-1 pattern?
Oh, yeah...

it looked like just a square wave. I will post my msq and the csv from the tooth logger in the morning.

[5.3LS10]

Here is the .msq file and the .csv from the tooth logger. I will take a picture of the scope output once I get it hooked back up.

[5.3LS10]

After using the composite logger I see the 36-1 signal.

[5.3LS10]

Also I did some more playing around with the O2 sensor issues. If I go to the tunerstudio project properties and change EGO sensor to narrow band Which brings up the EGO gauge with voltage it gets a rather linear output even in tunerstudio (which reflects what I was seeing on my voltmeter). But when I change the sensor back to wideband it goes back to an actual AFR and it continues to jump around.

I think there may be a setting issue with tunerstudio.

[5.3LS10]

bump anyone?

[Matt Cramer]

What calibration data are you using for the wideband?

[5.3LS10]

What calibration data are you using for the wideband?

I didn't think I had to use any for the jimstim. I thought when i used for example an LC-1 or LC-2 then I would have to specify a specific sensor. Where do I calibrate tunerstudio for the jimstim pot?

[Matt Cramer]

Use whatever data you plan on using on the car. I believe the default is for a narrow band and does not give a very smooth response.

[elutionsdesign]

Where do I calibrate tunerstudio for the jimstim pot?

I just did it, go to tools, un/lock calibrations and choose unlock (because the AFR calibrations are grayed out). Now you can go into calibrate AFR table and select the appropriate wide band, burn, relock calibrations.

[5.3LS10]

Where do I calibrate tunerstudio for the jimstim pot?

I just did it, go to tools, un/lock calibrations and choose unlock (because the AFR calibrations are grayed out). Now you can go into calibrate AFR table and select the appropriate wide band, burn, relock calibrations.

You most definitely deserve a high five for that one!! Thanks I had no idea that tunerstudio locked the calibration changes. When I was changing between narrow and wide band I was doing it under project properties and not the tools calibrate afr table spot.

Thanks to everyone so far for all the input.

Any one know for sure if jimstim 2.0.3 will simulate a LS rpm signal? I have heard of issues with v1.5 but I thought 2.0.3 fixed that.

Thanks again!

[5.3LS10]

Where do I calibrate tunerstudio for the jimstim pot?

I just did it, go to tools, un/lock calibrations and choose unlock (because the AFR calibrations are grayed out). Now you can go into calibrate AFR table and select the appropriate wide band, burn, relock calibrations.

You most definitely deserve a high five for that one!! Thanks I had no idea that tunerstudio locked the calibration changes. When I was changing between narrow and wide band I was doing it under project properties and not the tools calibrate afr table spot.

Thanks to everyone so far for all the input.

Any one know for sure if jimstim 2.0.3 will simulate a LS rpm signal? I have heard of issues with v1.5 but I thought 2.0.3 fixed that.

Thanks again!

My apologies for the confusion between 1.5 and 2.0.3. I was confusing hardware and software versions.... so maybe the jimstim cannot correctly simulate the ls1 wheel pattern?