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CAPT_BLOTTO 12-03-2021 07:31 PM

Won't idle
 
I'm still trying to get my Microsquirt setup working. Car will run with the throttle held open but will not idle at all.

It has the 850 TPS with the yoshifab adapter. Throttle is calibrated and shows 0% when my foot is off.

It has an LH 2.4 idle valve. Valve worked before with the 2.4 ECU.

MS is set to PWM valve closed loop. I don't know if that's the right settings.

What do I look at next to trouble shoot this?

CAPT_BLOTTO 12-03-2021 07:34 PM

1 Attachment(s)
Attachment 19341


Also here is the datalog from it running for a short time.

142 guy 12-03-2021 10:25 PM

Its not the cause of your problem; but, what frequency are you running? 92 hz seems to be the best setting for the Bosch 2 and 3 wire valves.

What have you got your warm PW set at for the valve? On my Bosch 2 wire valve, the valve is open at 0% and goes closed about 25% and then re opens around 40% going to full open around 70% - 90% PW. The normal practise is to have it operate in the 40% to 90% PW region. The 2 wire valve is voltage sensitive. The % values for open and close change with operating voltage so if 45% is open with the engine running and good voltage it may not be open during cranking when the voltage is low. You need to program the voltage sensitivity into Tuner Studio. If you have the three wire Bosch valve the positions are insensitive to the operating voltage.

You need to pull the idle valve off the car and look into the ports as you run the idle valve using the idle valve output test function in Tuner Studio. As you vary the PW you should be able to see the valve go open and confirm the start of opening and full opening % values. Yours may not match up with mine.

Tuning closed loop idle takes a lot of work. Start off using open loop. If you still have a mechanical air by-pass, use it to set a base warm idle speed. Get the rest of your tune and configuration settings into a reasonable state and then you can set the idle PW versus temperature curve for the idle valve to give you a good cold idle speed for warm up. If you have ignition control I suggest that you implement the idle advance function to help stabilize the idle speed. At the point that you have your tune perfect and a good configuration you can take a crack at trying to make closed loop idle control work.

Call back in a few months to tell us how it is going. While you are working on it, poke yourself in the eye with a stick so that you know there is something more painful than trying to perfect closed loop idle.

Dvroofer 12-03-2021 11:52 PM

Quote:

Originally Posted by 142 guy (Post 6235654)
Call back in a few months to tell us how it is going. While you are working on it, poke yourself in the eye with a stick so that you know there is something more painful than trying to perfect closed loop idle.

Exactly how I felt when I was trying to get going initially. I would probably follow advice above testing your valve. Try asking some of the veterans for help with a solid idle first. Everyone has been helpful getting me started. I turned my valve off and ended up ditching it opening the throttle a tad and starting from there.

CAPT_BLOTTO 12-04-2021 01:15 PM

I'm just trying to make it easy for myself. Maybe I'll just ditch it. I had closed loop and 124hz because that's what it was when I opened tuner studio.

I've also found there's something going on with my TPS. It has a good signal when the engine is off but as soon as I start cranking or get it running it's out of control. Wild swings up and down. It's going ± 20% while keeping it steady so I need to dig into that.

bobxyz 12-04-2021 01:47 PM

Here's how the 2-wire LH2.4 IAC valve behaves over ~10 minutes of my drive to work. The IAC pwm duty cycle is the white line on the bottom graph (click pic for bigger)

https://i.ibb.co/sHY6ZYw/LH2-4-Idle-Air-Control.png

The IAC valve runs at 97.7Hz (10.24ms) with pwm duty cycle varying between ~75% briefly at startup to ~38% lowest idle flow. In addition to idle speed, LH2.4 seems to adjust the idle air based on RPM too. The corner box in MLV shows ~20 seconds of idling at a stop light, with IAC varying around 41.5% at ~750rpm.

Full logs are here: https://www.dropbox.com/sh/bjr74pnng...L6mkEgPma?dl=0

DailyDriverMods 12-04-2021 02:36 PM

These settings work almost OEM-like on my MS3'd B230F, it was running LH2.4 originally.

https://tweakers.net/i/SfZQOdG1R83tF...toalbum_medium
(it's clickable)

142 guy 12-05-2021 04:05 PM

Quote:

Originally Posted by CAPT_BLOTTO (Post 6235734)
I've also found there's something going on with my TPS. It has a good signal when the engine is off but as soon as I start cranking or get it running it's out of control. Wild swings up and down. It's going ± 20% while keeping it steady so I need to dig into that.

+/- 20% is a 40% variation. If you have correctly calibrated your TPS in Tuner Studio to full closed and full open, a 40% variation in TPS signal is too much for vibration induced fluctuations unless something is broken in the TPS. I would start looking for problems in the signal path such as stray ground currents getting coupled into the TPS ground path and creating ground offset voltages.

CAPT_BLOTTO 12-20-2021 05:31 PM

Well I've made some small progress. Rewired all the sensors just to the sensor ground input. Having the grounds on the intake manifold was causing some sort of issue with the TPS.

I got it to run and even idle some. Now I'm seeing an issue with my AEM wideband. It's showing very lean on the MS and occasionally spikes to rich. The gauge however doesn't show that at all. It's showing full rich all the time. It's wired the white analog output from the AEM to the pink on MS. Is there anything I would need to change on EGO control? It's set to single wideband local input. I assume that's the pink input wire for MS.
Or do I need to ground the AEM to the same sensor ground?

linuxman51 12-21-2021 12:12 AM

you need to calibrate the afr table for the wideband as well, otherwise it's using the lookup table for a narrowband sensor and anything over 1v will be full lean. there's also that cool phenomenon of ground differentials.. so try and ground the wideband at the same point you're grounding the ms.

I generally run the idle valve around 97hz or there abouts, with a 'closed' value of like... 28 or so (I'd have to look), it's not actually closed at that point, but I've found no need to run it any lower than that. don't worry about the idle part so much until you've got your afr's roughed in (And/or tuned fairly well), otherwise it'll be a moving target. You can also turn on idle timing and use a + - from zero to add or pull timing based on what direction the idle is going.. timing will react faster than the valve will (And the valve isn't terribly slow) and helps smooth it all out.

culberro 12-21-2021 01:33 AM

Are you running a diode across + and - for the PWM valve? It reduces/removes the flyback voltage when the coil is de-energized.
(page 32) https://www.efisource.com/docs/Micro...DWManualRS.pdf

http://www.turbobricks.net/forums/sh...d.php?t=358452

And this, it adds a ton of stability. It was the only way I could get the big cam 5.slow to idle well and even idle along smoothly in gear.
Quote:

Originally Posted by linuxman51 (Post 6239752)
You can also turn on idle timing and use a + - from zero to add or pull timing based on what direction the idle is going...


CAPT_BLOTTO 12-21-2021 01:21 PM

Quote:

Originally Posted by culberro (Post 6239761)
Are you running a diode across + and - for the PWM valve? It reduces/removes the flyback voltage when the coil is de-energized.
(page 32) https://www.efisource.com/docs/Micro...DWManualRS.pdf

http://www.turbobricks.net/forums/sh...d.php?t=358452

And this, it adds a ton of stability. It was the only way I could get the big cam 5.slow to idle well and even idle along smoothly in gear.

I've seen conflicting things about the diode. I have some and can add it in.

CAPT_BLOTTO 12-21-2021 01:32 PM

Quote:

Originally Posted by linuxman51 (Post 6239752)
you need to calibrate the afr table for the wideband as well, otherwise it's using the lookup table for a narrowband sensor and anything over 1v will be full lean. there's also that cool phenomenon of ground differentials.. so try and ground the wideband at the same point you're grounding the ms.

Yep calibrating fixed it! It's "running" and "idling" now.

Still needs starting fluid to get started so I'm guessing the warm-up enrichment is way off.

it's also stupid rich. But I needed to get it to the point of the basic inputs and outputs functioning before beginning any tuning.

142 guy 12-22-2021 12:59 PM

If it needs starting fluid to start, that is not a warm up enrichment problem. That is a priming and cranking fuel pulse width problem. Once the engine fires and gets above the cranking versus running transition RPM then the fuel injection switches to the fuel equation and running off the fuel map with the warm up correction added into the fuel equation.

Don't spend time trying to refine your warm up until you have your base fuel map close to sorted out. The warm up correction is added to the pulse widths derived from the base fuel map values and if you end up making material changes to the fuel map you will screw up your warm up.

Alan29 12-22-2021 03:15 PM

I'd certainly turn off WUE as well at this stage. Dial in that idle when the engine is nice and warm then work on your fuel map as 142 stated.

142 guy 12-22-2021 05:16 PM

Quote:

Originally Posted by Alan29 (Post 6240342)
I'd certainly turn off WUE as well at this stage. Dial in that idle when the engine is nice and warm then work on your fuel map as 142 stated.

Good point about completely zeroing out warm up enrichment to start off with. If the car is running 'stupid rich', eliminating screwed-up warm up enrichment settings will prevent them from distorting the set-up of the basic fuel table.

Probably a good idea to zero out acceleration enrichment. If Blotto is still getting continuous noise on the TPS sensor it could be generating unplanned acceleration enrichment that he doesn't need.

CAPT_BLOTTO 12-22-2021 09:47 PM

Quote:

Originally Posted by 142 guy (Post 6240405)
Good point about completely zeroing out warm up enrichment to start off with. If the car is running 'stupid rich', eliminating screwed-up warm up enrichment settings will prevent them from distorting the set-up of the basic fuel table.

Probably a good idea to zero out acceleration enrichment. If Blotto is still getting continuous noise on the TPS sensor it could be generating unplanned acceleration enrichment that he doesn't need.

No fixing all the grounds to the sensor ground on the ms instead of some of them on the intake manifold cleared that up.


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