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Re: red 2003 VVT test mule Miata NB2 #27

Posted: Tue Sep 03, 2019 8:03 pm
by stefanst
alexander-n8hgeg5e wrote:
Tue Dec 18, 2018 12:26 pm
So you have 6 valves... 3 rounded and 3 not.
And they control 4 brake lines...
Abs means not esp, so... maybe not all wheels have to be controlled seperately
I mean if one of the front wheels block, maybe both of them get regulated.
I think best is figure out how they are hydraulicly wired.
A bit like a schematic. rounded ones could be some pressure release.
and the other ones for rising pressure or so.
I juuuust looked at this. Miata ABS has two separate lines for front wheels and only one line for rear wheels combined. There's also only on brake line going to the back of the car.

Re: red 2003 VVT test mule Miata NB2 #27

Posted: Wed Sep 04, 2019 2:49 am
by AndreyB
Things are very nice until about 2000 RPM. At 2000 RPM I start getting trigger errors :( Logs attached.

Re: red 2003 VVT test mule Miata NB2 #27

Posted: Wed Sep 04, 2019 3:34 am
by AndreyB
I've soldered pins to GND, CRANK and CAM pads and here is some logic analyzer data showing a miss :(

Re: red 2003 VVT test mule Miata NB2 #27

Posted: Thu Sep 05, 2019 1:42 am
by AndreyB

Re: red 2003 VVT test mule Miata NB2 #27

Posted: Thu Sep 05, 2019 2:09 am
by stefanst
russian wrote:
Thu Sep 05, 2019 1:42 am
Wooohoooo!
Awesome. When I heard the whoop-wooop behind you, even I, sitting on my sofa at home, had my heart skip a beat or two. Ambulance in this case is MUCH better than our friendly Jersey City Cops.

Re: red 2003 VVT test mule Miata NB2 #27

Posted: Thu Sep 05, 2019 2:13 am
by AndreyB
stefanst wrote:
Thu Sep 05, 2019 2:09 am
When I heard the whoop-wooop behind you, even I, sitting on my sofa at home, had my heart skip a beat or two.
I know! Totally unscripted whoop-wooop :)

Re: red 2003 VVT test mule Miata NB2 #27

Posted: Thu Sep 05, 2019 5:55 am
by Crazy Striker
Nice private off-road track you have here ;)

Otherwise congratulations, nice to see everything going well, especially the ETB

Gwendal

Re: red 2003 VVT test mule Miata NB2 #27

Posted: Wed Sep 11, 2019 1:33 am
by AndreyB
instant RPM does not work reliably - I am rolling back to "slow" RPM, will have to investigate instant RPM implementation

some idle PID games attached but I am a blind man in the dark here, PID tuning makes no sense to me :(

Re: red 2003 VVT test mule Miata NB2 #27

Posted: Wed Sep 11, 2019 1:56 am
by stefanst
russian wrote:
Wed Sep 11, 2019 1:33 am
instant RPM does not work reliably - I am rolling back to "slow" RPM, will have to investigate instant RPM implementation

some idle PID games attached but I am a blind man in the dark here, PID tuning makes no sense to me :(
Could you post a screenshot of your settings?
Are you using Electronics throttle to control idle?

Re: red 2003 VVT test mule Miata NB2 #27

Posted: Sat Sep 21, 2019 5:33 am
by AndreyB
Just revived my Frankenso setup - the benefits are SD-card logging and real time clock for log name timestamps.

Attached are SD card version of the logs - we might still have some gaps but should be pretty close to TS logs. That's with 1ms period of logging - seems to be running at around 60Hz.

Next steps: figure our why is idle so high, add air piping and wire MAF with a voltage divider, fix more minor annoying bugs, drive around the block.

Re: red 2003 VVT test mule Miata NB2 #27

Posted: Sat Sep 21, 2019 11:09 am
by stefanst
Simple observations:
Your MAP calibration is off. Should be around around 100kpa before cranking. 30 also seems low while running at 1800rpm or so.
AFRs are super-rich. Lean that out. It may help drop the idle a bit. If idle stays high, hold something (your hand?) in front of the throttle plate. Block it off. If the engine dies, the excess air comes from your throttle. If not, you have a vacuum leak.

Re: red 2003 VVT test mule Miata NB2 #27

Posted: Sat Sep 21, 2019 11:21 am
by Crazy Striker
If you are using the base VVT tune I think it is pretty rich at idle and low load and quite fine while running. At least it is what I observed

Gwendal

Re: red 2003 VVT test mule Miata NB2 #27

Posted: Sat Sep 21, 2019 11:03 pm
by AndreyB
MAP calibration: I've corrected adcVcc to 3.3 and MAP is now a bit different
Also corrected vbattDividerCoeff and vBatt is now matching my multimeter.

MAF is wired to the ECU: the output of this MAF is current not voltage so I have a 1K pull-down on my Frankenso.

I've noticed an issue with sticky ETB around zero, I believe that's part of my high idle - https://github.com/rusefi/rusefi/issues/943 - latest best log is also attached to this ticket.

But probably a vacuum leak as well since covered throttle still gets me 550RPM, engine does not die.

Re: red 2003 VVT test mule Miata NB2 #27

Posted: Sun Sep 22, 2019 6:46 am
by Crazy Striker
Do you still have the PCV valve connected ? The vacuum leak may come from it. Considering how loud is my idle screw on my mitata you should be able to easily spot the leak, or with the good old flammable liquid spray technique.
What is the position of your throttle body without any power ? Is it fully closed or do you need to apply reverse current in it to close it fully ? I observed that on my VDO ETB (For E46 3 series BMW) the butterfly is quite open at idle and need a good negative current input to close it

Gwendal

Re: red 2003 VVT test mule Miata NB2 #27

Posted: Mon Sep 23, 2019 4:32 am
by AndreyB
Thermostat or not?

idle RPM here is about 1800, a bit high but still.

radiator temperature drop from 77C to 50C so about 27C


Re: red 2003 VVT test mule Miata NB2 #27

Posted: Mon Sep 23, 2019 6:06 am
by Crazy Striker
What afr are you running at idle ? What is the CLT output ?

This engine heats up pretty quickly, even when driving softly, I don't know why but I was surprised to see the coolant reach 70° in less than 3 minutes.

Maybe it's just the fact that you're standing still and running at 2000rpm. Does the fan lower the coolant temperature while turning on ?

Gwendal

Re: red 2003 VVT test mule Miata NB2 #27

Posted: Mon Sep 23, 2019 6:07 am
by AndreyB
CLT sensor output is pretty close to what Flir and I/R thermometer read, within a couple degrees. Fan is running.

There is an opinion that it is about the thermostat - tomorrow I hope to change it.
Crazy Striker wrote:
Sun Sep 22, 2019 6:46 am
Do you still have the PCV valve connected ? The vacuum leak may come from it.
PCV is just an open hose but plugging it made no difference :( Leak is somewhere else.

Re: red 2003 VVT test mule Miata NB2 #27

Posted: Mon Sep 23, 2019 9:17 am
by kb1gtt
How close is this to your other Miata in the garage? Perhaps do a compare with that one? Also does it react this way when on the OEM?

Re: red 2003 VVT test mule Miata NB2 #27

Posted: Thu Sep 26, 2019 3:17 am
by AndreyB
VNH2SP30 "eBay red board" is getting really hot while engine is idling. PID seems to want to apply more and more duty cycle in the closing direction. Not sure what is the chain of events here. Shall I simply set minOutput to -20 and hope for the best?

Wiring setup could be seen here


Re: red 2003 VVT test mule Miata NB2 #27

Posted: Thu Sep 26, 2019 5:53 am
by Crazy Striker
Hi !

I've built a small test rig with an arduino and a VNH board to play withy throttle body and all the variables I can set for the PID, and noticed that if you do not calibrate the ETB potentiometer range, the I term lead to very high current because it cannot reach the desired position. I can monitor both voltage and current thanks to my lab bench, but I think you can use the current sensing output of the board to trigger a safety.

I now use 2 sets of PID parameters for each part of the ETB range, 1 for before the steady position (6% of opening) and 1 after this position and it solved the issue.

Gwendal

Re: red 2003 VVT test mule Miata NB2 #27

Posted: Thu Sep 26, 2019 9:38 am
by kb1gtt
Can you put a heatsink on it? Also what frequency or period is your base pwm? I'm also not liking your semi long wires and semi crappy connections to power and the etb. Those connections need to be low impedance.

Re: red 2003 VVT test mule Miata NB2 #27

Posted: Thu Sep 26, 2019 11:59 am
by AndreyB
kb1gtt wrote:
Thu Sep 26, 2019 9:38 am
Can you put a heatsink on it? Also what frequency or period is your base pwm?
Please provide a link to eBay or not eBay.

Tried 300Hz 800Hz 1600Hz no difference.

Re: red 2003 VVT test mule Miata NB2 #27

Posted: Thu Sep 26, 2019 3:58 pm
by kb1gtt

Re: red 2003 VVT test mule Miata NB2 #27

Posted: Sat Sep 28, 2019 2:38 pm
by AndreyB
Again playing with alternator duty cycle just to see if we can implement auto tune. Here VBatt uses custom firmware with ADC_FAST mode.

Noisy VBatt in fast logs :(

Re: red 2003 VVT test mule Miata NB2 #27

Posted: Sun Sep 29, 2019 7:36 pm
by AndreyB
VAG 1.8T ETB shape is suspiciously similar to miata ETB shape.

Top mounting holes just match - but I needed to to drill ETB to make holes bigger.

Lower holes do not match so ETB lower mounting area was cut off and a metal bracket pulls the lower side of ETB. This is now _rock solid_.

Re: red 2003 VVT test mule Miata NB2 #27

Posted: Wed Dec 11, 2019 6:43 am
by AndreyB
Burned a coil :( Some additional info at https://github.com/rusefi/rusefi/issues/1051


Re: red 2003 VVT test mule Miata NB2 #27

Posted: Mon Dec 16, 2019 3:56 am
by AndreyB
Just to write it down, Hall mode on microRusEfi 0.3:

R9=R15=C35=DNP
R18=R19=4.7K
R13=0R
R12=10K
R17=1.5K

Image

Re: red 2003 VVT test mule Miata NB2 #27

Posted: Mon Dec 16, 2019 4:29 am
by AndreyB
Now trying to run same car on microRusEfi "pre-assembled" 0.4.5

R9 I would have to remove (useful 4.7K resistor)
C35 I would have to remove and discard this capacitor
R15 I would have to remove and discard this resistor

R18 and R19 I would have to add 4.7K
R13 I would have to replace 10K with 0R
R12 10K stays as is
R17 I would have to install 1.5K

Re: red 2003 VVT test mule Miata NB2 #27

Posted: Sat Feb 08, 2020 8:05 pm
by AndreyB
Second reason why I got the cutter - one day we shall have NB2 P&P.

Re: red 2003 VVT test mule Miata NB2 #27

Posted: Thu Feb 13, 2020 1:48 pm
by AndreyB
New data point: cheap $10 eBay coil.

With normal coils I have reliable USB connectivity. This specific cheap coil breaks USB connection every time I click one single spark!

Can we learn something from this coil? Should we survive it same as we survive proper coils?

Somehow stock ECU runs with it just fine. Swapping this coil has NOT fixed my current rusEfi starting issue :(