Warm up noise - input sought

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MS Spider
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Warm up noise - input sought

Post by MS Spider »

Hi All,

MS = V 3
TS v3.0
MS Extra 3.4.2
14point7 wideband
LS coil pack running wasted spark
450 cc DSM injectors
Cheery Crank mounted Hall Sensor

I am struggling with a VERY rough cold start that produces near constant Syn loss (reason 2).
Attached please find a composite and tooth log.
Strangely (well, I think so) is that this seems to disappear as soon as the engine is warm. The engine runs fine and I can drive around normally with no noticeable issues. As I type this, I realise that I MAY have sync loss issues that I cannot feel.

My original thoughts were that I have a noise issue related the warm up. I have unplugged almost every sensor, one a time and nothing changes. The Hall crank signal seems to be the issue. I am using shielded wire that is away from noise.

I am at a loss for hardware solutions so I have started to explore ignition noise filtering in TS. I have 'Noise Filter Enabled' with very low values, 118us from 0 rpm to 3000 and this seems to help a little, not much. Any more than that has no effect.

'Tach Period Rejection' seems like a good option to ignore some of the phantom trigger events however when I turn this on the idle drops to 500 (almost stalls) and the sync loss remains.

So.....any help is much appreciated. I keep reading and making changes which has lead me to problems in the past.

Cheers,

Jordan
grom_e30
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Re: Warm up noise - input sought

Post by grom_e30 »

the tooth log is pretty ugly you are missing teeth that should be there hence the extra long teeth every so often, it also looks like you are triggering off the wrong edge of the signal with the long and long ish tooth after.

i dont think noise filtering will help id be looking at adjusting the pots / sensor gap
1990 bmw 320i daily driver with m20b25 ms3 sequential fuel, 380cc injectors, d585 coil near plug, home made cam sync, launch control, fan control, vss, homebrew egt logging what's next????
MS Spider
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Re: Warm up noise - input sought

Post by MS Spider »

Thanks!

I had a chance to get the MS box open and start playing with the pots. I started with both adjusted 6 turns counterclockwise and turned them clockwise.

R56 seemed to help a little at 4 turns CW. I also tried changing the Ignition capture to falling edge which seemed to help quite a bit although the engine was starting to warm up at that point and I not sure which factor changed the behaviour.

Watching the tooth logger I was still seeing some ugliness so I attempted to adjust hysteresis. Turning the pot CW did not change the logger much although the engine slowed and stalled with a little backfire. The car would not start after this. Changing Ignition capture back did not help. returning the hysteresis pot to 6 turns CCW did not help. I ran out of play time and packed up for the day.

No logs from today :oops:
MS Spider
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Re: Warm up noise - input sought

Post by MS Spider »

Update:

Sensor gap is .3 mm. Spec is 1mm +/-. I have some concerns about the gear teeth shape and thickness (think bicycle sprocket) but it has run well in the past so I will assume it will run again.

Pots:
R56 tuned 6 turns CCW = no RPM signal detected. R56 turned 4 turns CW and it reads a signal!! So far so good.
Adjusting hysteresis does not seem to have an effect, or I do not know how to check. I started with 6 turns CCW and turned 1/2 at a time all the way through 6 turns trying to start at each setting. Still will not start.

I have noticed that 'Not Synced" is illuminated while cranking and does not go out. What exactly does 'Synced' refer to. MS is reading crank RPM........


Going back to basics on this I have realised that my Vbatt does not register what is actually on the MS board. I believe this can lead to troubles with large injectors, which I have.

Ignition on, car not running:
Voltage measured at battery terminals (in trunk) = 12.3V. OK.
Voltage measured between S12 and Ground on proto board = 11.88V. Not perfect, but I assume acceptable.
Voltage Vbat as displayed in TS= 10.2V. Not good.

After reading several posts and consulting the manual I am unsure what to do.

Option 1

Tools>Calibrate Battery Voltage adjust 'Supply Voltage at 0" up until Vbat=11.88V =actual voltage on the MS board as measured between S12 and board ground

Option 2

Calibrate voltage to another measured value. If so, what? Voltage at injectors?

Option 3

Something else entirely because I clearly do not understand what I am doing?
MS Spider
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Re: Warm up noise - input sought

Post by MS Spider »

Hi all,

The saga continues!

It runs! Sort of.... Log attached.

It seems I was a little too cavalier with setting changes and managed to fry an ignition module by changing the Spark Output setting to Going Low without fully understanding the repercussions.

New module in place and we are back to where we started. Starts but crank signal is messy with lots of resets.

R56 has been adjusted all the way CCW and slowly turned CW until the tooth logger reads a signal.
R52 was adjusted all the way CCW and turned CW until the car stalled with little to no change in signal quality.

I have tried changing the ignition capture to falling edge with no change.

More reading and I am now considering this paragraph from the manual .
Note for the Hall/optical/points circuit: The LED inside of the opto-isolator is fired by a signal provided by the ignition system. The pulses existing on an ignition, especially when pulled directly off of the coil primary, can spike to very high voltages. The return path of the LED is terminated to jumper pad XG1. This return path can either go directly to the board ground (by placing a jumper from XG1 to XG2), or, the return can be brought out of one of the jumper slots on the DB-37 connector (like SPR4 for pin #6), and then grounded with a separate wire on the DB-37 connector, thus isolating the ground. Note: for the ECU to work on the stimulator, then the XG1 terminal needs to be hooked to XG2, and right now we are doing stimulator testing, so install a jumper from XG1 to XG2.
When you install the ECU, if you need isolation because the tach signal is resetting the ECU (for those installs tapping right off of the ignition coil (-) terminal), then you can remove this jumper and connect XG1 to SPR4, and ground this pin (#6 for SPR4) with a separate return wire. Note: if you are using a tach output from an aftermarket or many OEM setups, the tach signal is a nice +12V pulse - these will work fine with the XG1 terminal jumpered to XG2 in the install. Again: for testing right with the stimulator, hook XG1 to XG2. Later, after you install this on your vehicle, if you have reset problems, then remove this jumper and jumper XG1 to SPR4, and bring out a separate return ground wire to the ignition module/distributor on DB37 pin #6.

You may also need to do this if the Hall sensor input is noisy in the vehicle. To reduce noise, run the ground from the Hall sensor to one of the jumper slots on the DB-37 connector (like DB37 pin #6 for SPR4), then connect SPR4 to XG1. Remove the jumper to XG2. (Note that you will have to ground XG1 with a jumper wire to run on the stim.) Twist the signal wire (DB37 pin #24) and ground wire (DB37 pin #6) together all the way to the ignition module, this will further reduce noise in the signal.
I am not sure I understand the last paragraph. I understand that the Hall grounds comes into the MS box through pin6 and is connected to XG1. Jumper from XG1 to XC2 is cut to separate the Hall ground from the MS board ground. And then what? Why do I run the pin6 wire to the ignition module? Should I not ground it to the chassis?

The MS unit is now out of the car and on the bench. I will see where I can get with the Stim and some bench testing. If possible I will follow the instructions listed above to try and isolate the noise.

Any and all insights and suggestions appreciated.

Cheers,

Jordan
slow_hemi6
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Re: Warm up noise - input sought

Post by slow_hemi6 »

First you said you were tuning the pots, ie. you are using the VR/normal input. If that is the case then you are not using the OPTO input and none of the info you quoted has any relevance to your install.
Where in the MSextra manuals did you find that quote?
Find the Manuals up top under Quick links: Manuals. :RTFM:
Cheers Luke
MS Spider
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Re: Warm up noise - input sought

Post by MS Spider »

Hi Luke,

Thanks for responding.

Text from here: http://www.megamanual.com/ms2/V3assemble.htm

Further reading has me looking at this page and I see an issue. http://www.msextra.com/doc/pdf/html/MS2 ... e-3.4.html

I have the current version of the VR circuit for the Hall sensor (tachselect jumped to vrin and tsel jumped to vrout)

HOWEVER I ALSO have the pull up resistor soldered into my board. This the setup for an open collector Hall Sensor.

My Cherry Hall sensor HAS the internal resistor. I will remove the jumper and resistor from vrin.

(Time lapse)

OK, Just removed the jumper and adjusted R56 so that R54 reads 2.50V

In the car tomorrow and I'll test..........
MS Spider
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Re: Warm up noise - input sought

Post by MS Spider »

Minor update.

Back in car and have the same problems. Tach in signal is UGLY during warm up and OK once warm.

Sensor gap checked.
Pots adjusted.
Wiring rechecked.
Batt Voltage now reading OK

Noise filtering has some effect (Slight improvement).
Ignition settings>Noise Filtering>Primary Tach = On and settings as listed in tool tip for 36-1 (200us@500pm 13us@7500rpm). Adjusting this up leads to worse performance. Adjusting this down and the engine will stall.
Tach period rejection= Off . turning this on and the car runs very rough and will stall.

I will continue to research noise filtering.
MS Spider
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Re: Warm up noise - input sought

Post by MS Spider »

Argh!!

New frustration. Car will not start and when I stop cranking the communications die, TS says offline. I need to enter Settings and detect the Bluetooth unit to start again.
MS Spider
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Re: Warm up noise - input sought

Post by MS Spider »

OK. we are up and running. Cleaning the plugs got me started again.

Much more reading on noise and I now believe eve that noise can come from MANY sources within an engine bay including cylinder events. I am now trying to consider the engine MS as a system and trying to work through a big picture assessment of what is happening. With this in mind I started the car, suffered through an UGLY warm up of sync losses and rpm fluctuations due the to the Idle valve being all over the place trying to catch up to a crazy tach in signal. Note, unplugging the Idle Valve improves the warm up experience as the rpm is stable, I still have all the sync loss but none of the wild rpm fluctuations. For now, I am treating the idle air valve fluctuations as a symptom of the Tach In signal noise. Feel free to comment if you think otherwise.

Once warm the car settled down again (as it always has) and I went for a tuning run. The original tune was OK (I have been driving this car for 5 years with MS) but an hour of driving with auto tune and everything was smooth below 4,000 rpm (average fuel map cell change of 5). If I strayed into a section of the Fuel Map where I had not tuned, and the car car ran rich and sputtered, I would experience the sync loss again.

Current operating theory is that a bad tune is part of the problem and I will try a cold start again tomorrow and see how the Tach In signal is with a good base tune.

As always; thoughts, conjecture, previous experiences and wild guesses entertained and appreciated.

Cheers,

Jordan
MS Spider
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Re: Warm up noise - input sought

Post by MS Spider »

OK, tune is now fine at low rpm and this has no impact on cold start.

I have a log of the transition from rough cold start to a stable run. The transition happens at 353 seconds. ANY thoughts on what is happening at this transition is much appreciated. I am at a loss!!!!

Also attached is a tooth log of the same transition.

Help!!!
Matt Cramer
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Re: Warm up noise - input sought

Post by Matt Cramer »

It's failing to see real teeth. Start by trying a tighter sensor gap.
Matt Cramer -1966 Dodge Dart slant six running on MS3X
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