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Old 01-26-2010, 01:04 AM   #1
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Default Need some comment on noisy CLT signal

Hi All,

I need some opinions on my coolant and air temp signal.
Here is a screen shot.


Is the noise on in the CLT and MAT signal normal?

Thanks.
-Raj
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Old 01-26-2010, 01:16 AM   #2
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I don't remember my CLT or IAT's jumping up and down like that at idle/cruising. Maybe under load but that does not seem normal.
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Old 01-26-2010, 05:31 AM   #3
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Have you grounded them at the same point and if so, where? It might not be a decent ground.

What's up with your AFR?
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Old 01-26-2010, 09:49 AM   #4
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I haven't done anything to the stock ground points. I will try cleaning them all. I also have low-z injectors running on MS-2, I am afraid that the noise is from the injector flyback dampening circuit.
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Old 01-26-2010, 09:51 AM   #5
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That's how mine look. It's jumping up and down what <1? The resolution with MS-II is pretty rubust. With a range of -40F to +257F vs. -40F to 215F, I noticed the same thing when I upgraded to MS-II, it seem to read the sensor and updates faster than before with a more accurate real-time display of the values it's reading.
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Old 01-26-2010, 11:15 AM   #6
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set your min and max values for CLT and MAT to something reasonable like 0-235 for CLT and 0-120 for MAT and see the squiggles go away.
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Old 01-26-2010, 12:09 PM   #7
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Quote:
Originally Posted by Braineack View Post
That's how mine look. It's jumping up and down what <1? The resolution with MS-II is pretty rubust. With a range of -40F to +257F vs. -40F to 215F, I noticed the same thing when I upgraded to MS-II, it seem to read the sensor and updates faster than before with a more accurate real-time display of the values it's reading.
I forgot what the magnitude of the noise is. Is the Max and Min values displayed for the windowed region?

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set your min and max values for CLT and MAT to something reasonable like 0-235 for CLT and 0-120 for MAT and see the squiggles go away.
Where do you set the min and max? Is it in the Tunerstudio/MSQ file or is it in the Megalogviewer?

Thanks.
-Raj
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Old 01-26-2010, 12:22 PM   #8
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Quote:
Originally Posted by redrider706 View Post
I forgot what the magnitude of the noise is. Is the Max and Min values displayed for the windowed region?

Judging by your min/mac values in your log, those spikes look to be at most +/-2. I wouldn't worry about it. The ADC values that it's reading from the sensor are more minute (adj.), I haven't changed a thing, setup wise, and noticed the same CLT and MAT "spikes" as you are seeing from upgrading from MS-I to MS-II.
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Old 01-26-2010, 12:30 PM   #9
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Quote:
Originally Posted by Braineack View Post
Judging by your min/mac values in your log, those spikes look to be at most +/-2. I wouldn't worry about it. The ADC values that it's reading from the sensor are more minute (adj.), I haven't changed a thing, setup wise, and noticed the same CLT and MAT "spikes" as you are seeing from upgrading from MS-I to MS-II.
OK. Thanks
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Old 01-26-2010, 03:18 PM   #10
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Quote:
Originally Posted by redrider706 View Post
I forgot what the magnitude of the noise is. Is the Max and Min values displayed for the windowed region?



Where do you set the min and max? Is it in the Tunerstudio/MSQ file or is it in the Megalogviewer?

Thanks.
-Raj
MLV.

pull down "calculated fields"
select "Field Min and Max"
type in the field name EXACTLY as it is in the left side selection (spaces, quotes, symbols, etc)
type in a minimum value
type in a maximum value
hit OK and watch your graphs rescale to something useful.
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Old 01-26-2010, 07:46 PM   #11
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Looks like it's idling nice and smooth, a little high maybe, but looks good to me.

I'm of course assuming that the AFR readings are incorrect.
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Old 01-26-2010, 07:57 PM   #12
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Quote:
Originally Posted by Ben View Post
Looks like it's idling nice and smooth, a little high maybe, but looks good to me.

I'm of course assuming that the AFR readings are incorrect.
Most of the time it was idling great at about 1500 rpm. My tech edge WB wasn't working and I had to turn off EGO correction. I am working on that and once I get that going I can set the idling AFR and try to get a handle on closed loop idling. Then it will be VE live tuning time.

Does my process sound right?

-Raj
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Old 01-26-2010, 08:05 PM   #13
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Why is it idling so high?
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Old 01-26-2010, 08:38 PM   #14
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I am not sure why. I think that it might be too rich at idle. I wanted to set the VE using the wide band and then play with the idle air screw to set the idle rpm with the idle value closed. Then I will play with closed loop idle.
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Old 01-26-2010, 09:08 PM   #15
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Gochya. I didn't know if you had intentionally set idle that high, or if you had a known vac leak or something.

You might want to run through this thread to help get up to speed on working with closed loop idle
Megasquirt MSEXTRA and MS3EFI &bull; View topic - Closed loop IAC control: Documentation

Obviously we don't know where your fueling is, but lean conditions actually tend to result in a higher idle, and typically uneven. Your idle is good and even, it's just high. You should be able to idle at 900 rpm, around 14:1, pretty smoothly--once you start nailing it in.
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Old 02-01-2010, 02:18 PM   #16
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Ok. Got the wideband O2 working. I couldn't get the MSQ that I put together to work. So, I started form a fresh DIY's 94-95 MSQ and changed the settings to fit my setup (550cc low Z injectors and different fan port). This seems like a good starting point. The car idles at 1200 RPM and the AFR is OK at idle.

My TPS signal is oscillating a little (Between 0% and 1%). Any amount of calibration doesn't seem to fix it. This in turn triggers TPS accel enrichment at idle and the car stumbles a little. It idles OK when I switch off accel enrichment.

I will try to setup the MAP and TPS based accel enrichment later today or tomorrow. In the mean time I want to setup closed loop idle. I am going to read the document Ben posted and follow it.

Can anyone post what the valve frequency should be for the idling valve on a 1.6L throttle body? Mine is a 1.8 swapped car with the original throttle body.

Thanks.
-Raj
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Old 02-01-2010, 02:24 PM   #17
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Here is my MSQ and datalog of the run.

-Raj
Attached Files
File Type: zip DIY-Based-init-tune.zip (223.8 KB, 24 views)
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Old 02-01-2010, 02:34 PM   #18
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Quote:
Originally Posted by redrider706 View Post
Ok. Got the wideband O2 working. I couldn't get the MSQ that I put together to work. So, I started form a fresh DIY's 94-95 MSQ and changed the settings to fit my setup (550cc low Z injectors and different fan port). This seems like a good starting point. The car idles at 1200 RPM and the AFR is OK at idle.

My TPS signal is oscillating a little (Between 0% and 1%). Any amount of calibration doesn't seem to fix it. This in turn triggers TPS accel enrichment at idle and the car stumbles a little. It idles OK when I switch off accel enrichment.

Set your "off" TPS ADC value so it's a few points above to set point you actually measure. You should make the WOT setpoint a few points lower than the actual as well. This should filter out some of the error.
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Old 02-01-2010, 03:49 PM   #19
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Great idea. Will do that.

Thanks.
-Raj
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Old 02-01-2010, 04:31 PM   #20
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I have to do something similar because when my throttle is closed mine will read 0% or 6% depending on the current battery voltage output.
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