Dialing in idle (Stock 1.6 w/ DIYPnP)
#1
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Hi,
First of all, I would like to apologize in advance for any cringing that occurs while you read this. I am a noob to all of this.
Ok, so just for clarification, I will provide the whole story of my build in as much detail as possible. So, I have a stock 1991 miata that is bone stock besides a "high flow intake" from Racingbeat. I am planning on going turbo in the future and the most logical first step seemed like installing a standalone ecu. I bought and built a DIYPnP. All the solders were good and it powered up on the first try. At first my car wouldn't start on the base tune. Upon investigation I found out that I somehow forgot to jumper the connections for the injectors. So, after that was fixed, I had a properly working DIYPnP with the base tune for a 90-93 miata. I installed an Innovate MTX-L wideband and powered the stock ecu from it, using the narrowband output. Next, I put the megasquirt back into the car. Everything worked as normal and I started the car up. It started after about 2 seconds of cranking, but it kicked and sputtered and sounded very bad. Come to find out, I had forgotten to set the EGO type to narrowband. After I fixed that, I started it back up (Note: The idle control was still set to "Warmup only"). This time still took about 2 seconds to start. When it first started it sputtered for a few seconds (Loads of un-burned fuel in the cylinders that were missing previously) and then smoothed out. However, it was idling at about 1750 rpms and as it warmed up it rose to about 2000-2100. Afr started in the high 9's and rose to about 13.5:1 at 180 degrees. I tried changing to closed loop idle. When I started it back up, it kicked and sputtered how it did before. Rpms were around 5-600 and fluctuating a lot. It sounded like it was only running on 2 cyl and it was smoking badly out of the exhaust. When I reverted back to open loop, I had the same results. At this point, I decided I would put the stock ecu back in and seek help. When I started it back up on the stock ecu, it missed for a few seconds and then started idling correctly. There was a lot of un-burnt fuel left in the cylinders, and afterword there was a lot of water in the exhaust.
Extra details : I had tried setting the tps (stock) to 0 and unplugging it. Also tried editing the pwm %'s. Neither of these seemed to make any difference in idle.
Thank you in advance for the help, tune file will be included. CurrentTune.msq
First of all, I would like to apologize in advance for any cringing that occurs while you read this. I am a noob to all of this.
Ok, so just for clarification, I will provide the whole story of my build in as much detail as possible. So, I have a stock 1991 miata that is bone stock besides a "high flow intake" from Racingbeat. I am planning on going turbo in the future and the most logical first step seemed like installing a standalone ecu. I bought and built a DIYPnP. All the solders were good and it powered up on the first try. At first my car wouldn't start on the base tune. Upon investigation I found out that I somehow forgot to jumper the connections for the injectors. So, after that was fixed, I had a properly working DIYPnP with the base tune for a 90-93 miata. I installed an Innovate MTX-L wideband and powered the stock ecu from it, using the narrowband output. Next, I put the megasquirt back into the car. Everything worked as normal and I started the car up. It started after about 2 seconds of cranking, but it kicked and sputtered and sounded very bad. Come to find out, I had forgotten to set the EGO type to narrowband. After I fixed that, I started it back up (Note: The idle control was still set to "Warmup only"). This time still took about 2 seconds to start. When it first started it sputtered for a few seconds (Loads of un-burned fuel in the cylinders that were missing previously) and then smoothed out. However, it was idling at about 1750 rpms and as it warmed up it rose to about 2000-2100. Afr started in the high 9's and rose to about 13.5:1 at 180 degrees. I tried changing to closed loop idle. When I started it back up, it kicked and sputtered how it did before. Rpms were around 5-600 and fluctuating a lot. It sounded like it was only running on 2 cyl and it was smoking badly out of the exhaust. When I reverted back to open loop, I had the same results. At this point, I decided I would put the stock ecu back in and seek help. When I started it back up on the stock ecu, it missed for a few seconds and then started idling correctly. There was a lot of un-burnt fuel left in the cylinders, and afterword there was a lot of water in the exhaust.
Extra details : I had tried setting the tps (stock) to 0 and unplugging it. Also tried editing the pwm %'s. Neither of these seemed to make any difference in idle.
Thank you in advance for the help, tune file will be included. CurrentTune.msq
#9
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The idle speed is pretty stable (doesn't fluctuate noticably), I just need to get the idle speed lower. What I found so far is that, to lower idle, you lower the idle duty. (Note: Im talking about when it idled at 2000 ish here, not the sputtery 2 cyl idle that spat smoke) My plan is to restart with the base tune (So I can get back to the non-horrible idle), and go from there making small adjustments 1 at a time. Thanks and Sorry for any confusion
#10
Boost Czar
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you literally have a table that says "at this clt temp, open the valve this much"
that's it.
so if you want to lower the idle speed, lower the duty cycle in that table until you get the RPM you want. But remember base on ambient conditions, that RPM might move 500-1000RPM.
otherwise, if you spent the 10 minutes to tune closed loop, all youd have to do is move your RPM target to the desired RPM.
that's it.
so if you want to lower the idle speed, lower the duty cycle in that table until you get the RPM you want. But remember base on ambient conditions, that RPM might move 500-1000RPM.
otherwise, if you spent the 10 minutes to tune closed loop, all youd have to do is move your RPM target to the desired RPM.
#11
![Default](https://www.miataturbo.net/images/icons/icon1.gif)
you literally have a table that says "at this clt temp, open the valve this much"
that's it.
so if you want to lower the idle speed, lower the duty cycle in that table until you get the RPM you want. But remember base on ambient conditions, that RPM might move 500-1000RPM.
otherwise, if you spent the 10 minutes to tune closed loop, all youd have to do is move your RPM target to the desired RPM.
that's it.
so if you want to lower the idle speed, lower the duty cycle in that table until you get the RPM you want. But remember base on ambient conditions, that RPM might move 500-1000RPM.
otherwise, if you spent the 10 minutes to tune closed loop, all youd have to do is move your RPM target to the desired RPM.
#12
![Default](https://www.miataturbo.net/images/icons/icon1.gif)
Closed loop idle isn't as hard as people would have you believe.
Getting it to work 90% of the time in 90% of conditions is pretty easy.
Getting it perfect is what people can struggle with.
This should help you:
Mega Miata: Basic idle settings
You need to wire in your wideband to tune your engine.
If you can build a DIYPnP, I'm sure its not beyond you to modify your car's wiring harness so you can switch between your O2 controller's wideband and narrowband outputs when changing ECUs.
Tuning the Acceleration Enrichment is probably the easiest part though, so at least you have that to look forward to
Getting it to work 90% of the time in 90% of conditions is pretty easy.
Getting it perfect is what people can struggle with.
This should help you:
Mega Miata: Basic idle settings
You need to wire in your wideband to tune your engine.
If you can build a DIYPnP, I'm sure its not beyond you to modify your car's wiring harness so you can switch between your O2 controller's wideband and narrowband outputs when changing ECUs.
Tuning the Acceleration Enrichment is probably the easiest part though, so at least you have that to look forward to
#13
![Default](https://www.miataturbo.net/images/icons/icon1.gif)
Closed loop idle isn't as hard as people would have you believe.
Getting it to work 90% of the time in 90% of conditions is pretty easy.
Getting it perfect is what people can struggle with.
This should help you:
Mega Miata: Basic idle settings
You need to wire in your wideband to tune your engine.
If you can build a DIYPnP, I'm sure its not beyond you to modify your car's wiring harness so you can switch between your O2 controller's wideband and narrowband outputs when changing ECUs.
Tuning the Acceleration Enrichment is probably the easiest part though, so at least you have that to look forward to
Getting it to work 90% of the time in 90% of conditions is pretty easy.
Getting it perfect is what people can struggle with.
This should help you:
Mega Miata: Basic idle settings
You need to wire in your wideband to tune your engine.
If you can build a DIYPnP, I'm sure its not beyond you to modify your car's wiring harness so you can switch between your O2 controller's wideband and narrowband outputs when changing ECUs.
Tuning the Acceleration Enrichment is probably the easiest part though, so at least you have that to look forward to
#14
![Default](https://www.miataturbo.net/images/icons/icon1.gif)
Closed loop idle isn't as hard as people would have you believe.
Getting it to work 90% of the time in 90% of conditions is pretty easy.
Getting it perfect is what people can struggle with.
This should help you:
Mega Miata: Basic idle settings
Getting it to work 90% of the time in 90% of conditions is pretty easy.
Getting it perfect is what people can struggle with.
This should help you:
Mega Miata: Basic idle settings
#15
![Default](https://www.miataturbo.net/images/icons/icon1.gif)
Don't try to tune idle settings until the engine is at normal operating temperature and your VE table values and ignition timing have been validated.
Load in the standard map from DIY Autotune
You can download from this link:
https://www.diyautotune.com/diypnp/a...93-16b6-mt.zip
Choose the one for 240cc injectors and load it into your MS
Make sure your ignition is set correctly using a timing light and the method below:
https://www.diyautotune.com/tech_art...ing_how_to.htm
Read all the articles here:
https://www.diyautotune.com/tech_art...h_articles.htm
and here:
Megasquirt2_Setting_Up-3.4
Load in the standard map from DIY Autotune
You can download from this link:
https://www.diyautotune.com/diypnp/a...93-16b6-mt.zip
Choose the one for 240cc injectors and load it into your MS
Make sure your ignition is set correctly using a timing light and the method below:
https://www.diyautotune.com/tech_art...ing_how_to.htm
Read all the articles here:
https://www.diyautotune.com/tech_art...h_articles.htm
and here:
Megasquirt2_Setting_Up-3.4
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itsMikey
Insert BS here
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09-05-2015 02:56 PM
holy driver
MEGAsquirt
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