Hello everyone! I am facing two very odd issues right now which I have spent numerous hours trying to resolve along with my tuner. Little background info, I am running a MS3Pro PnP on my 2003 Miata SE with a flyin miata turbo kit, DW 650 Injectors, along with other goodies. I have wideband installed along with IAT for the Megasquirt. My current issue is the motor not being able to keep idle when fans kick on (Flyin miata upgraded fans and crossflow radiator), along with this I am facing a extreme lean condition whenever I get hard on the throttle. The weird part is I am making perfect power as long as the throttle is eased into. Pretty much everything has been replaced or checked to attempt to resolve the issue, IACV, vvt rebuild, vvt solenoid, 60 psi fuel pressure under load, and tested for vacuum leaks in intake and exhaust. This only seemed to start when I installed the ecu. I will attach the tune file and datalog file below in hopes that someone would take a look. I am super puzzled and would love any help. Thank you in advance.

 

Out of curiosity, does your "tuner" work for an actual tuning shop, or is it just a friend? How much time did you spend tuning the fuel table, because at a glance I'd be looking to dial that in further. EGO seems to be pulling or adding 10% or more fuel in most places. I would also flatten your MAT fuel correction for the time being since that's pulling some fuel as well.

Have you tuned your acceleration enrichment at all to try to correct the lean condition?

Which FM fans are these? Are they PWM, because the output pin on the fan menu is a PWM pin, but they are set to operate as On/Off. I assume they're pretty strong fans, you might simply need to add more duty cycle when they kick on. I want to say I had to add like 12-15% idle duty cycle when I was tuning AC Idle up on my car last summer.

 

Regarding the fan and idle, I installed a massive 40 Amp draw SPAL fan, and it always killed idle when it turned on.
But on the MS3 you can set a fan delay of around a second after the coolant reaches the trigger temp, as well as setting a high idle.
When the fan is triggered the idle goes up, stabilizes over the 1 sec delay, and then when the fan kicks on it does not kill the idle, just wobbles it.
But, with the FM PWM fans I don't know if there are other tricks required, as mentioned above.

 

Replying to both Simba and Icedawg. He is a actually proper tuner, Jeffs Tuning and Performance in Ocala Fl, he has tuned a handful of miatas on MS and done many other cars. We have spent about 15 hours on the fuel table trying to dial it in, I would trust that he has most things well dialed for the car. I was reading another thread on here that states that the TPS percentage should be turned down from 100% to 15% in the AE settings to resolve the issue. I have yet to try this due to the fact that it seems like a way to get past the problem rather then fix whatever it might be.

Regarding the fans, they are the Flyin Miata Stage 1 Fans, any tips to dial them in other then turning up the idle? Seems like they draw so much power.

 

For the fans, I'm not suggesting you raise the idle RPM. I'm suggesting you increase the duty cycle of the idle air control valve (IACV) to offset the extra load of the fans. IIRC your tune has the ECU add about 3% duty cycle when the fan kicks on. I'm suggesting you try something larger. Maybe bump that up to 6% or 10% and see if that helps. You will need to dial in the value a bit, if you use a value that's too large it'll overshoot the target RPM and the ECU might try to compensate by pulling timing, but that's not a huge concern in the short term. If you try a couple values and get logs of the fans cycling on and off post them on here and we can look at them.

Personally I would extend the time that AE is active instead of the activation threshold. You activated it in that log, but it doesn't seem like it lasted long enough. This could act as a bandaid if you're just compensating for a poorly tuned fuel table, but AE itself isn't a bandaid and is necessary to keep the car from bogging or leaning out when you stab the throttle.

Are you under the impression that something other than the tune is causing it to lean out? It seems like you threw a lot of parts at it to fix this issue even though the car ran fine on the stock ECU.

 

Also, just so other people can see these, I'm going to post the spark map and fuel table. IMO these look pretty bad and I'd be disappointed if I paid for a dyno tune (assuming this was on a dyno) and ended up with this. Not trying to **** all over this, but if you "spent about 15 hours on the fuel table trying to dial it in"...

VE is one thing, but IDK why the ignition map jumps 7 degrees like that at 150 KPA or why there's only a single degree of change from 150->200 KPA around 5K RPM

 

Regarding stage 1 fans: They draw an insane amount of current when they turn on. You'll need to add like a 1 second delay, bump the idle 50-100 RPM, and increase duty before they turn on. The last ones I did on a Link took quite a bit of fiddling to get ok, and I still felt it needed more fiddling. The owner eventually got the PWM Stage 2 kit, and those are awesome.

 

I can't speak to the fan situation, but I'm trying hard to understand the logic of the AE table and settings.

It's been a long while since I fooled with those setting but I ditched the MAP and TPS-based AE settings and dove head-first into the dangerous world of EAE. Those were tricky as hell to deal with but I got my car to behave itself (for the most part) with transient conditions. I think you have something deeper going on than just "When I stomp on the throttle, the AFRs go lean". It seems that any manipulation of the throttle is causing a lean spike of some sort or another.

I just took a cursory look, but you won't solve what you're seeing by manipulating the VE table. JMHO

 

I attempted to flatten my MAP and extend the AE time which seemed to make my issue worse. Now whenever I get on the throttle it bogs longer and is much more jolty. I was kinda assuming it was a mechanical issue but seems like it definitely could be tune based. Regarding the spark and fuel tables, I'm assuming he didnt fully get everything done because we are still having this issue. Not to fear, he hasn't fully charged me

 

I guess I should have described the issue a little more in depth and some other observations I have made. It's less that it dies when I get on the throttle but more of a dying issue when I tap the throttle to where TPS reads 1 percent, then it dies. I also noticed that when it does bog out while driving the Accel enrichment table % goes up when I first get on the throttle and it feels good but after half a second the enrichment goes back to 100% and the car goes lean.

 

I have really looked at a map in like 14 years, and i can tell that's bonkers.

 

@CamReno If you want to try it, I've attached an updated copy of your tune.

Here's what I did. I wasn't able to gather a ton of data from that log. Having said that, here's what I did.

• Smoothed out the ignition timing in boost and pulled some timing out of it. I based this on the map I run with 91 octane.
• Lengthened the idle up time from 100 ms to 500 ms to allow the idle up to take more effect before the fans kick in. I also raised the IACV duty cycle from 3% to 5%. It might need more though
• Smoothed the fuel table and added fuel when getting into boost. This table should be rescaled IMO.
• Pulled fuel in AE but extended the duration. The car went fully rich and then fully lean in that log, so hopefully this and the fuel table changes will keep things a bit more steady. A TPSDOT lockout would be nice here, but I couldn't find a setting for that.

 

Thank you sir! I just did a little bit of driving to see how it feels. Unfortanetly it still feels the same, so weird to me that these changes dont make a affect. The fans are much better though! I will attach the log below

 

Well to be fair these changes are hard to estimate because the logs have very little meaningful data. It's all transient (IE Accelerating) which makes it hard to tell what values make sense. A log with 10 seconds of steady cruise at a handful of different points in the RPM range would be much more helpful.

That last log just seems lean everywhere in boost. IAT Corrections are pulling fuel everywhere. In the first log EGO is adding/removing like 20% at various points.

Normally it's recommended to turn all those corrections off when dialing in the fuel table for the first time so you're not chasing your tail. I would be pretty careful driving this as is, because the fueling seems all over the place. If you're not up to operating temp, like in that last log, then EGO isn't going to try and help track targets and you're just on an untuned fuel table (assuming nothing else is going on).

You can try the tune below which has a good amount of fuel added and IAT corrections leveled out (IE it won't pull fuel). I think the req fuel value is wrong for the size of injectors you have but I didn't want to mess with that right now.