New to the Miata scene and extremely new to tuning. I recently picked up a turbo 2000 NB1 with a Beer Money ECU. Been starting to figure out tuning and so far, so good.

I’ve been running in to an issue where after a short cruise, it leans out (primarily at cruising speeds) at around 16.5 to 18.5. Also, idles around 15.5 when warm as well.

I’ve gone in and messed with the VE table quite a bit and it doesn’t really seem to have any effect with the issue.

Like I said, I’m very new to all of this. I can give any information needed.

TIA

Sean

 

Post a tune and a datalog, it’s probably a trim table somewhere decreasing fuel for air temps or EGO shuts off during higher temps

 

this.

I would find this table, completely zero it out, and only tune it when it's warm out and you actually need to lean the motor out at a given temp because your EGO keeps pulling fuel to hit your targets once at these temps and your fuel map is tuned otherwise.

 

So coming back to this a little late. I put the old tune back on that was on the vehicle and it isn't really leaning out anymore after restart. I took it on a drive to the parts store today (new clutch going in this weekend) and it was driving pretty good. Idles at a pretty consistent 14.5 but if i clutch in, it'll lean out above 17+ for a short second.

Both the original tune and the tune I had been recently running are attached. For some reason my datalogs aren't saving. Ill try to take a cruise later and see if i can get it to work.

I'm planning on throwing in a upgraded fuel pump and FF 725cc PnP injectors in it here shortly so i know it'll have to be re-tuned but clutch is priority right now. Would just like to be able to not stress about driving it.

Sidenote, recently idle started sitting at roughly 1,500rpms randomly one day, when normally its idling at around 1,100rpms.

I don't have any local tuners that will tune a Beer Money ECU so I'm stuck trying to learn how to tune myself, which i really enjoy learning or going with a MS ECU, with a big trip coming up , its out of my budget.

TIA, Sean.

 

I've tuned a million miatas and would love to help you, but I spent 10 minutes trying to figure out how to view your tune, couldn't figure it out. It's some beer money firmware that I don't have, won't let me download it automatically, and their site is beyond my skill level. If you can attach the .ini file, that'd help a bunch.

 

Unfortunately, the .ini file isn' acceptable file format for this website. I don't know how else i can send it to you.

 

Curly, try the file I've linked here and just rename it from a .txt to a .ini

I was able to get the tune loaded up with this. I just glanced at some of the menus, but it's definitely different from Megasquirt or Speeduino. I might poke around more tomorrow.

For now I'd just say you might benefit from setting your idle cells in the VE table to the same value. It looks like there's some pretty major jumps in the values around idle.

 

As I typed this, I think I found the "smoking gun", as it were, so skip to the end, but the following still relates:

Yeah that sorta got it, looks like a couple errors, so I can't edit your tune and send it back to you, or at least I wouldn't suggest it.

I don't love Megasquirts, that's why I moved to a Link. They're good, but now there's better IMO. My brain is telling me you just have Megasquirt hardware with a similar TS interface, but I know it's more complicated and hopefully a company with a name like Beer Money Motorsports is relying more on the "Motorsports" part of it's name to develop ECUs vs. the "Beer Money" part. I digress. I'm not sure if we're the premier forum for tune help in general, and maybe BMMs has it's own forum to discuss tuning issues, but this little hiccup is already a bit frustrating. I'll do what I can for now.

There's some things I see that you might change for fueling. For closed loop fuel correction, you have to be below 1000rpm to activate "idle" correction, which if you're now idling at 1500 but normally 1100, you're never below. So three things about that: A, fix your idle. B, fix your CL fuel settings, C, it doesn't really matter since all the settings are the same. But you can change your idle to have +/-10% instead of only 5%, which may be what you need. If you want to go from an idle of 15.5 to your target of 14.7, you'd need that entire 5% allowance, so any leaner and you'll need more. Even out your fuel table as Sim said, then take logs of both idle and cruise with CL fueling set to +/-10%, and see what your correct rate is. If it's constantly 5-10% in a region, you can add that directly to the base VE table so it doesn't have to correct as much. Goal is to get it around +/-5% or less in most circumstances. If you make some changes and you're now using -10% when cold, and +10% when warm, then I'd say you need to see what parameter is affecting it, and make a trim table for it. There's already an IAT and ECT trim table available, but there may be a way to create a custom trim table for fuel temp, for example.

I don't see the typical IAT adjustment setting, I think it's "IAT multiplier"? But you've got that zero'd out, so that shouldn't be affecting it.

Eureka! I think I found it. Your "warmup fuel manual multiplier" is trimming up to 11% fuel as it warms up. Except it's called "ECT multiplier" in the drop down menu. Change anything below 1.0 to 1.0, and see if that helps, along with the above changes.

 

I will give all of that info a shot! I really appreciate you going through my tune!

One last thing is the car has a hell of a time trying to start when its cold. Battery and started test great, but I almost have to feather the throttle after a few tries of starting it to get it to turn over!

Again, I appreciate all the help!

 

obviously the fueling is off now that's colder and you havent tuned your cranking fueling. depending on your fuel map, it could be that opening the throttle a little is leaning it out while cranking when youre otherwise flooding it.

 

For a while I couldn't figure out why my car would lean out when it sat at idle. I knew heatsoak was probably the reason but then I started to really sit down and figure out why. I never considered the iat density table. And what I noticed is as iat rose the car would lean out. I kept chasing it with VEtable numbers and got no where. So then I looked at my iat density table and noticed as temps rose i was pulling way too much fuel causing it to lean out so what I did was flatten the curve passed a certain point and watched my afrs and also coolant temps. Waited until the fans kicked on and when a change happened whether up or down I made a small adjustment. And doing that worked. The coolant Temp stayed steady, and when the fan did kick on afrs never got out of control. I was happy with those results.