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Old 09-20-2014, 04:02 PM   #21
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Braineack, I really respect your MS knowledge, but I have to disagree on some of the points that you have raised. If you would look at the log file in Megalogviewer, I believe you will see that the WBO sensor is not going out.

4ddiction, starting from the top...

20 is no where near correct for a 95 Miata with OEM injectors... I believe most people with NA 1.8's are using 235cc for the injector size, which nets out to a req_fuel value of 12.8.

I opened up the last msq file which you posted... Your previous value for req_fuel of 11.4 is too low because you have the injector size set to 265cc. 265cc is right to the NB2 VVT engine injectors, but not the NA injectors.

You Idle VE values are too low, compared to your VE table. You have VE values of about 50 in the idle region, yet your Idle VE table has values in the high 30's. That is a difference of about 20%...

Looking at the "lean out" log file... The PW numbers of ~17ms are way too low for reasonable AFR with a NA 1.8 and stock injectors. My NB2 idles with PW numbers of about 2.9ms. Now that is with slightly larger injectors, but that actually means your PW numbers should be higher than mine. I would say > 3ms as a baseline minimum.

When the AFR dips down to 16-17, it isn't because of a bad WBO... If you look at the PWM Idle Duty, you can see that it is varying between 30-37. This results in the MAP values changing, followed by the AFR values slightly behind those events because there is lag naturally in the AFR readings.

4ddiction, I am glad you got the car to idle. Since none of us is in the OEM ECU tuning business, we can get away with using "strange" baselines, then compensate in other areas. However, you will be better off in the long run setting up your tune with more reasonable baselines. If not, you won't be able to compare the values in other people's tunes, because yours are so skewed.

Good luck with it!
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Old 09-20-2014, 04:23 PM   #22
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May be off topic but since on the subject of required fuel in this conversation:

When running NB injectors at NB fuel pressure rates, what are your injector flow rates?

Seems to me it should be about 300cc assuming no boost. NB2 is a little higher 311cc I think.

The injectors are listed as 254cc and 265cc but thats at 3bar. If running 60 psi, why would you input 45psi rates?
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Old 09-20-2014, 04:38 PM   #23
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Quote:
Originally Posted by noname4me View Post
Braineack, I really respect your MS knowledge, but I have to disagree on some of the points that you have raised. If you would look at the log file in Megalogviewer, I believe you will see that the WBO sensor is not going out.

4ddiction, starting from the top...

20 is no where near correct for a 95 Miata with OEM injectors... I believe most people with NA 1.8's are using 235cc for the injector size, which nets out to a req_fuel value of 12.8.

I opened up the last msq file which you posted... Your previous value for req_fuel of 11.4 is too low because you have the injector size set to 265cc. 265cc is right to the NB2 VVT engine injectors, but not the NA injectors.

You Idle VE values are too low, compared to your VE table. You have VE values of about 50 in the idle region, yet your Idle VE table has values in the high 30's. That is a difference of about 20%...

Looking at the "lean out" log file... The PW numbers of ~17ms are way too low for reasonable AFR with a NA 1.8 and stock injectors. My NB2 idles with PW numbers of about 2.9ms. Now that is with slightly larger injectors, but that actually means your PW numbers should be higher than mine. I would say > 3ms as a baseline minimum.

When the AFR dips down to 16-17, it isn't because of a bad WBO... If you look at the PWM Idle Duty, you can see that it is varying between 30-37. This results in the MAP values changing, followed by the AFR values slightly behind those events because there is lag naturally in the AFR readings.

4ddiction, I am glad you got the car to idle. Since none of us is in the OEM ECU tuning business, we can get away with using "strange" baselines, then compensate in other areas. However, you will be better off in the long run setting up your tune with more reasonable baselines. If not, you won't be able to compare the values in other people's tunes, because yours are so skewed.

Good luck with it!
Fuel Injectors - Miata Turbo FAQ

According to that, my tan 94-97 are 265 cc not sure if that changes anything.

Updated current tune.
Attached Files
File Type: msq CurrentTune.msq (178.0 KB, 133 views)
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Old 09-20-2014, 11:15 PM   #24
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Quote:
Originally Posted by 4ddiction View Post
Fuel Injectors - Miata Turbo FAQ

According to that, my tan 94-97 are 265 cc not sure if that changes anything.

Updated current tune.
I stand corrected... the 1.6L and 99-00 1.8L NB injectors are both 230-240cc/min, but as you said the 94-97 and 01-05 injectors are 265cc/min.

I would then expect your req_fuel to be set to the same as mine, which is 11.6. Also, your VE values and injector PW for the idle regions should be close as well (VE 45-50, PW's of about 2.9 once out of WUE).

Try the new values out and log the car idling, then post up your log file.
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Old 09-21-2014, 11:26 AM   #25
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Here is a screen shoot from the baseline tune that DIYAutotune supplies with their MS2 PNP's for the 94-97 Miata 1.8L's. It is only a baseline tune, but should be close for a stock 1.8. (Disregard the coloring of the VE table numbers.) Actual VE numbers around idle will vary based on ignition timing and idle control valve setup though.

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Lean out on idle.-screen-shot-2014-09-21-9.21.12-am.png  
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Old 09-23-2014, 05:44 PM   #26
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running fine. damn PID

Last edited by 4ddiction; 09-24-2014 at 02:24 AM.
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Old 09-25-2014, 09:58 PM   #27
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Were you able to get you tune working correctly? If not, post up your latest msq file and logs.
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