Miata runs worsE than stock after dyno tune
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The car was running fine with the stock ecu.
After the dyno tune I have a contant miss from 5k-6k rpm then it smooths out.I also use to start the car and go. Now it has to warm up or it will stall.
Even after warming up the idle still hunts sometimes and drops down as low as 250 rpm at times.
The tuner didn't seem to know what he was doing at times.
I have a MS2 with sequential injectors built by brain. How do I check the settings on the MS2 is correct and using this feature?
How do I check to make sure all the idle related settings are correct?
He also tuned it to run in open loop only so it doesn't even use the 02 (narrow or wide) sensor reading. Is that a good or bad thing?
I'm boosting 5-6 psi w 84mm pistons (8.6 compression) and I think I should be able to make more than 140hp. And that number is on the higher rpm so to get there I have to fight through the misfire from 5-6k rpm.
Thanks in advance.
After the dyno tune I have a contant miss from 5k-6k rpm then it smooths out.I also use to start the car and go. Now it has to warm up or it will stall.
Even after warming up the idle still hunts sometimes and drops down as low as 250 rpm at times.
The tuner didn't seem to know what he was doing at times.
I have a MS2 with sequential injectors built by brain. How do I check the settings on the MS2 is correct and using this feature?
How do I check to make sure all the idle related settings are correct?
He also tuned it to run in open loop only so it doesn't even use the 02 (narrow or wide) sensor reading. Is that a good or bad thing?
I'm boosting 5-6 psi w 84mm pistons (8.6 compression) and I think I should be able to make more than 140hp. And that number is on the higher rpm so to get there I have to fight through the misfire from 5-6k rpm.
Thanks in advance.
#2
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HP is probably not too far off for the boost.
I think you went to the dyno far too early. At the dyno, time is limited -- you need to be focused on what you can't tune yourself. Things such as idle tuning and mixture tuning should be done in advance. There are great tools available, especially for mixture tuning. Use MegaLog. Also, send Tobin the money he deserves for giving us such a great tool.
Once idle and mixture are sorted (using a conservative spark map -- such as a default from MSPNP), THEN go to the dyno and focus on spark.
Use your wideband.
I've been turbo since April. I've put ~3,000 miles on the car. Idle is perfect. Fuel is perfect. Boost control is perfect. Plus, I now know my MS inside and out. I am now ready to go to the dyno and, because I'm up to speed, will get my money's worth.
I think you went to the dyno far too early. At the dyno, time is limited -- you need to be focused on what you can't tune yourself. Things such as idle tuning and mixture tuning should be done in advance. There are great tools available, especially for mixture tuning. Use MegaLog. Also, send Tobin the money he deserves for giving us such a great tool.
Once idle and mixture are sorted (using a conservative spark map -- such as a default from MSPNP), THEN go to the dyno and focus on spark.
Use your wideband.
I've been turbo since April. I've put ~3,000 miles on the car. Idle is perfect. Fuel is perfect. Boost control is perfect. Plus, I now know my MS inside and out. I am now ready to go to the dyno and, because I'm up to speed, will get my money's worth.
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The reason I took it to tune so early was because I was hoping they would be able to dial everything in for me. Since I didnt know how to tune myself. Time wasn't limited either because I was scheduled @ 7pm after they are closed for reg business. Was there until 12am when dude gave up.
You think 305cc is too small?
You think 305cc is too small?
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You need more compressor. Low compression does not pay off until 250whp or so. On my car I make terrible numbers until I hit 250whp, then it looks great. I make 242whp on a dynojet at 11.5psi, 275whp at 13psi, 310whp at 16psi. I also have compressor efficiency on my side, but I think the general rule is the same. Get rid of that little blower and move some air.
I hate when I see lurkers like yourself in this sittuation. Get more involved, make a build thread with your thoughts, and post. People think this forum is rogue, but we could have saved you some heart-ache.
Post your log and msq too.
I hate when I see lurkers like yourself in this sittuation. Get more involved, make a build thread with your thoughts, and post. People think this forum is rogue, but we could have saved you some heart-ache.
Post your log and msq too.
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I haven't done a log yet.
But here's my msq.
I'm a lurker mainly because the advice I received before was to throw money at the problem. When I said I wanted to fix the problem w/o throwing more variables into the mix a moderator confirmed I should get a ms. And that's putting it nicely. Mostly, I see a few ppl with knowledge while most ppl on here likes to sling insult because they are too stupid to know any better.
Hopefully, with the amount of ppl using megasquirt on this forum I would get some useful advice this time instead of the usual sophomoric response.
But here's my msq.
I'm a lurker mainly because the advice I received before was to throw money at the problem. When I said I wanted to fix the problem w/o throwing more variables into the mix a moderator confirmed I should get a ms. And that's putting it nicely. Mostly, I see a few ppl with knowledge while most ppl on here likes to sling insult because they are too stupid to know any better.
Hopefully, with the amount of ppl using megasquirt on this forum I would get some useful advice this time instead of the usual sophomoric response.
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I dont see anything inherently wrong that would cause the miss.
you're pushing a lot of timing, so if the AFRs are good you can't really blame the MS for the low power, unless the timing was never synced (ie the MS is demand X° and actually producing Y°)
but the idle settings dont look good. I've posted a methodology on how to fine tune the idle settings.
you're pushing a lot of timing, so if the AFRs are good you can't really blame the MS for the low power, unless the timing was never synced (ie the MS is demand X° and actually producing Y°)
but the idle settings dont look good. I've posted a methodology on how to fine tune the idle settings.
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If you're going to stick with 5-6PSI, you should be running stock compression. OTW, do the "hustler" and add some air.
No shortcuts with MS in my opinion. You have to learn it. I recommend tuning idle first. It'll get you started, and it's impossible to break anything. Do a search. Lots of threads with idle tuning methods.
No shortcuts with MS in my opinion. You have to learn it. I recommend tuning idle first. It'll get you started, and it's impossible to break anything. Do a search. Lots of threads with idle tuning methods.
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Thanks guys. I'll do a search on tuning the idle.
I was a little worried about frying the ms.
I tried to upload a new program on my camaro once and fried the pcm.
Very tempted to get the 400hp rotrex supercharger after I get everything sorted out with the jrsc. But on the other hand this is my beater car I drive to work with. That amount of money and time could be spent on my classic car that's been collecting dust the past year.
I was a little worried about frying the ms.
I tried to upload a new program on my camaro once and fried the pcm.
Very tempted to get the 400hp rotrex supercharger after I get everything sorted out with the jrsc. But on the other hand this is my beater car I drive to work with. That amount of money and time could be spent on my classic car that's been collecting dust the past year.
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when i first bought my ms1 i read and read on tuning and didnt understand anything at first. it wasnt until i started actually plugging in numbers and seeing cause and effect that i could actually figure out what i was doing. just keep at it and go slow...you'll get it
the only thing i fried is an igniter cause i forgot to reload my tune after i reflashed firmware and had the spark setting wrong.
the only thing i fried is an igniter cause i forgot to reload my tune after i reflashed firmware and had the spark setting wrong.
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1. Learn your min/max idle duty %. You can do this two ways, the first being using idle valve test mode and bumping the duty up and down until you no longer see a noticable change in engine speed. remember the values, for a 90-93 you'll see it around ~25-62%. Aslo make sure to remember the RPMs these duty values obtain. The second method is using the Warm-up only mode and doing the same thing, just make sure you are doing it in an area that your CLT temp is sitting at. You should have one of your dashboard gauges displaying the idle PWM% so you know exactly what the MS is outputting.
2. Once you learn these values, plug them into your PID closed loop idle control parameters. So Idle Open Duty %, Idle Valve closed Duty %, RPM with valve closed, and RPM with valve open.
3. Now I like to start tuning, first, make sure your RPM targets are flat across the board for now, try 1000RPM to start. Now, turn PID values all to zero. Turn on your headlights and a/c blip the throttle and upset the idle and it will probably lock at >2500RPM. you can turn them off now. Now, start increasing the I value. When you slowly add I, you'll notice the RPMs slowly come down towards your target. Do this until you're within ~50RPM of your target...you'll notice the Idle PWM% moves in large chunks so it can only get close enough. Next start increasing P, cycle things like the headlights and a/c, the P term is used to reach your target faster when something causes it to move from your target...you should end up with a term that's above, maybe even double, that of I. Reduce it if you start to oscillate. Lastly you can increase D term, It dampens the effect so you dont overshoot the target when P and I are driving it up to the RPM target. You shouldn't need much.
This is the quick and dirty method and should get you rolling smooth and stable within a few minutes. Make sure the rest of the parameters are tuned to your liking, such as the TPS trigger, dashpot, delays, PID lockup settings, etc.
2. Once you learn these values, plug them into your PID closed loop idle control parameters. So Idle Open Duty %, Idle Valve closed Duty %, RPM with valve closed, and RPM with valve open.
3. Now I like to start tuning, first, make sure your RPM targets are flat across the board for now, try 1000RPM to start. Now, turn PID values all to zero. Turn on your headlights and a/c blip the throttle and upset the idle and it will probably lock at >2500RPM. you can turn them off now. Now, start increasing the I value. When you slowly add I, you'll notice the RPMs slowly come down towards your target. Do this until you're within ~50RPM of your target...you'll notice the Idle PWM% moves in large chunks so it can only get close enough. Next start increasing P, cycle things like the headlights and a/c, the P term is used to reach your target faster when something causes it to move from your target...you should end up with a term that's above, maybe even double, that of I. Reduce it if you start to oscillate. Lastly you can increase D term, It dampens the effect so you dont overshoot the target when P and I are driving it up to the RPM target. You shouldn't need much.
This is the quick and dirty method and should get you rolling smooth and stable within a few minutes. Make sure the rest of the parameters are tuned to your liking, such as the TPS trigger, dashpot, delays, PID lockup settings, etc.
That's what I found for tuning idle from braineack. I tried looking at tunerstudio and could not find a idle valve test mode or PID closed loop idle control. Are they located under the tab labeled "more settings"
After I find out the above information, where do I go to start the tuning? Is it with warm up wizard?
I'm really at a lost here. It's like being given something with no manual or start up guide. Or at least none that I could find and understand.
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Last edited by Halcyon; 08-11-2011 at 02:09 PM.
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I found the idle valve test mode. There's no min or max, just a run and home. When I turn on test mode the rpm goes up to 3k rpm regardless if I put in the value 10 or 150.
What am I doing wrong?
What am I doing wrong?
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Their website boast 400hp and some of the local shops here tells me good things about it. Don't want to go with a turbo since it's what I use to drive to and from work. More fun with a supercharger.
Driving the fx45 to work everyday is getting boring and the other camaro need a new optispark. So hopefully I can get this tune figured out.
Driving the fx45 to work everyday is getting boring and the other camaro need a new optispark. So hopefully I can get this tune figured out.
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