[rusEfi] Miata NA 1996, 1.8L stock (#7)

[spags]

Hi tomiata,

I've solved the ICV noise on my 94 miata, it turns out the hum is not the ICV it's in the airbox. Touch the airbox while running and you'll feel it. I think its caused by a harmonic with the icv frequency and the intake chamber.

Here's the link to the fix, works for me and hasn't broken yet.
http://rusefi.com/forum/viewtopic.php?f=3&t=729&start=30#p12431

As for the WBO, maybe double check your grounds, I hear those things tend to be sensitive to inconsistent grounds.

EDIT: Just had to say this after seeing the video of your car running, kickass yet another miata!!

[kb1gtt]

Fancy tool for finding and tracking noise http://m.harborfreight.com/mechanics-stethoscope-69913.html?utm_referrer=direct%2Fnot%20provided or the lower cost approach is to put your eat on a scree driver handle while you put the tip on the engine parts that you want to hear.

[tomiata]

Thanks, doing the "set_idle_solenoid_freq 500" seems to have eliminated the hum while running. But, now I can hear a 500Hz faint buzz sound coming from the ICV when the engine is off. I think I had the freq set to 250 before and didn't notice it when the engine was not running.

I'm trying to figure out the WBO. It's not showing good data yet.

I can start fairly well when warm and idles ok. If I adjust the fuel tables manually with set_whole_fuel_map, it changes the idle rpm. Setting to 4 makes it idle at about 1400rpm, setting to 6 makes it idle at about 1100 rpm. I don't understand this.

[AndreyB]

First of all, I really need to turn idle solenoid off while engine is not spinning - that's https://sourceforge.net/p/rusefi/tickets/117/

I've actually spend some time trying to tune idle today. I did experience the same thing when I was LOWERING fuel and the RPMs were going UP. I cannot explain it

I've started with 12ms giving me 1400 rpm (image how rich it was when you read the final value), I then went down to ~6ms and RPMs went to 1700. Step by step I was lowering fuel until some AFR values appeared on the display (my controller shows 0.0 if outside of the 9-19AFR range), I was also lowering idle_pwm to lower the idle rpms

Long story short, my results on the neon: ~900rpm idle with 2.8 ms fuel and idle_pwm 350

I'd suggest go lower and lower, until it dies. Once it does, you know you were too lean. Too rich does not stop the engine while too lean does stop it pretty fast.

[puff]

shouldn't EFI consider how lean/rich the mixture is when calculating ignition timing?

Long story short, my results on the neon: ~900rpm idle with 2.8 ms fuel and idle_pwm 350

what was the afr? what was the AFR after it changed from zero?



another theory: you were running too rich - explains bad o2 readings mentioned by tomiata, some fuel was going away unburnt to exhaust. by reducing injection time you sorta offset timing a bit. (shifting it away rom valve overlap?).

[tomiata]

Yes, I'm sure I'm running too rich. I smell gas, and my family tell me I smell like gasoline after I've been out working on the car.

[tomiata]

I did roughly the same procedure as @russian:

Long story short, my results on the neon: ~900rpm idle with 2.8 ms fuel and idle_pwm 350

And got down to 1.1 ms fuel and idle pwm 320, going lower killed the engine. My WBO showed a lambda down to 1.25, but doesn't change much through the process. I don't trust it yet. (I wonder if it got coated with unburned fuel or moisture and not giving good data. I had put it in my other car to test out, and it showed what looked like reasonable data.)

But, it won't start again after tuning down to these leaner values. I had to bump back up to 5ms of fuel and pwm to 400 or so to start up again. And then could tune down to lean again. Did that a couple of times.

Wrestling with usb serial connections for TS and console is a pain in linux. Spags, are you dealing with that in your setup? I saw your video with you using a linux laptop.

[AndreyB]

I did experience the TS issue today - https://sourceforge.net/p/rusefi/tickets/118/

[tomiata]

This thread has some example timing maps for the Miata 1.8L engine:

http://forum.miata.net/vb/showthread.php?t=237921

[AndreyB]

I think TS issue is here (that's in the rusefi.ini file):

#if CELSIUS
intake = scalar, F32, 8, "°C", 1, 0.0
#else
intake = scalar, F32, 8, "°F", { 0.01 * 9/5 }, 3200.00
#endif

so I am providing value in CELSIUS, but looks like the conversion is not right (the { 0.01 * 9/5 }, 3200.00 ) part

Any chance you would want to figure it out?

[meXanicus]

My version

Code: Select all

#if CELSIUS
      intake = scalar,  F32,8,"°C",1,0.0
#else
      intake = scalar,  F32,8,"°F",{1 * 9/5},32.0
#endif

TS calculates so. For example, 30 degrees Celsius, then 30 + 32 = 62 * 9/5 = 111.6. I do not know how to say that the TS must first multiply and then add 32
P.S. I do not understand English very well, so excuse me for google.translate.

[tomiata]

I'm back after a long break. From updating to latest firmware I'm running again. And I have a working WBO now.

I was able to start from a cold engine just now, and it runs fairly smoothly. A bit of a hiccup ever 5 or 10 seconds. AFR shows 9 to 10 range. Idle RPM sits steady around 1900. Changing idle_pwm has no effect now which is strange. Any known problems relating to that?

[AndreyB]

Idle RPM sits steady around 1900. Changing idle_pwm has no effect now which is strange. Any known problems relating to that?

Nope, as far as I know idle_pwm should work

[spags]

Hi tomiata, good to have another miata running the board!

The code for set_idle_pwm was changed to make more sense at some point. Now it takes a value between 0-100 and it will ignore out of bounds values.
I found that 40 makes mi car idle at around 1200, 35 is more like stock.

[tomiata]

Thanks a lot, that was it. set_idle_pwm at 28 puts me to idle at 1000.

[spags]

Awesome,

Mine requires about 10% more. I wonder if it's because of the temperature difference.

Are you running the solenoid frequency at 500? Wonder if that would have to do with variation.

[tomiata]

Hello after a long absence. Remember the clutch squeal? I just replaced the clutch and think I see the root cause. I think the throw out bearing was seizing up occasionally and grinding against the pressure plate. I put in a new clutch, fly wheel and throw out bearing, and other parts and got it running again.

See the groove cut into the fingers of the pressure plate.

IMG_20160107_215622~2.jpg (606.39 KiB) Viewed 23282 times

Hopefully I can try out rusefi again soon.

After a few rounds of trial and error and
speculation, I got a good tip from here:
http://forum.miata.net/vb/showthread.php?p=7158314#post7158314
And isolated the problem to the clutch, disabled the clutch safety interlock and I can start without scaring the neighborhood.

Now I can get a decent start on rusefi with no "horrible" sounds. For added flair I put the frankenstein in a box....

The attachment IMG_20141002_204826.jpg is no longer available

... and got lots of help from russian and kb1gtt. Thanks!

[kb1gtt]

It your no longer scaring the neighbors, how are you going to advertise your doing cool stuff

Good to hear the progress. What is the next step?

[tomiata]

I need get it legal again with inspection and license.

[AndreyB]

One of the last tabs on the current rusEfi console now allows you to test injectors and fuel pump - these you would hear from your driver seat. Spark is a bit more complicated but could be tested as well.

On the pictures from your fresh logs note how top two lines - the trigger signal - always get wider after the first cycle with spark and fuel? Do you have any theories for what it is? Could it be a backfire causing the engine to suddenly slow down once you try igniting stuff? Could it be the the spark output wires are flipped?

That's all my ideas for now I see the perfect trigger input. I see 7ms fuel pulse which is OK. I see that after the first cycle something changes. What does not make much sense is why is it after full cycle and not after a first spark, if it would be a wrong coil it would probably be right away not just after four sparks?

[tomiata]

Thanks Russian, I'll check my wiring again, and do more testing.

[tomiata]

Yep, that was it. The igniter wires were swapped. It started up just fine and I drove around the block. Getting it to start again after running for a bit is difficult. I don't have a wide band o2 sensor on yet. But, it's good to have it going again after. I'll get the wide band on and work on some tuning next.

[AndreyB]

Wow, I am pretty proud of figuring this out

[tomiata]

This is nice. I was able to start from cold and get idle to work with setting idle position to 35. Other than that it's the default firmware settings.

[video][/video]

[Abricos]

Congratulations!!!

[kb1gtt]

Cold you say, but you also say TX

Couple of us are more northern, and we have gotten to do some testing at much colder temperatures. The cold starts have gotten much better. Good to hear you're making progress. Keep up the good work.

[tomiata]

I'm trying to hook my wbo signal to afr input on pin inp10/PA7. After assigning the pin in TS, rusefi shows the error:

FATAL error: ADC mapping error: input PA7 for AFR already used?

I thought that input was unused. Any ideas?

[AndreyB]

I have just changed the error message and I hope that it would now show what is the pin used for. Can you please give it an hour to re-build and try with firmware 20160423?

[tomiata]

Here is the error message with updated firmware:

FATAL error: ADC mapping error: input PA7 for AFR already used by IAT?,

Where is IAT getting set to use PA7?

[AndreyB]

I do not see it in the files, what does it show
?

Can you post your whole CurrentTune.msq if it's not there?