Help needed from MSP gurus (charts inside)

C

codex

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2016 Mazda3 Hatchback
I recently dyno'd my 03.5 MSP. Mods are FMIC, SRI, ATP wastegate, catless midpipe. I believe my MSP was flashed by the P.O.. I put down 176.2 WHP, which I think is respectable for the stock ecu. My concern is with the AFRs that I got from the runs. I always knew when driving that I would not go WOT until after 4k rpm because it would just run like crap. Well, this chart shows why, it is crazy lean until somewhere around 4k rpm then crazy rich afterwards.

So, now I need to understand better what is going on. Is this just the way the stock msp ecu operates? I'm thinking that I may have a problem somewhere else. It feels like timing is too far advanced (would this cause lean?) beacuse onces it hits the switch over point around 4k rpm, the sound of the engine changes. Also there is a very noticeable increase in power.

What I need to know, is this normal? Is it possibly a problem with metering, o2, vacuum leak, etc?
Also, if this is normal will an SSAFC fix this or do i need the SSFTC (assuming that it is timing which is causing the lean AFRs)?

Thanks guys!!

ps: the chart also shows PSI, any idea why there are so many ripples in the boost? Is my new ATP wastegate bad?
 

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looks like a normal oem ecu tune to me.

and, i wouldn't call it "crazy lean" since the signal is bouncing around 14.5, which is stoichometric air-fuel ratio. what it shows is that the stock ecu is looking at the o2 sensor signal for the lower rpms, and a predetermined fuel table for higher rpms. any custom ecu will be able to tune that out for optimal power.
 
I thought 14.5 (it spikes to over 15) for 9psi was wayyyyy too lean, am I wrong? Can someone maybe help me understand what the ecu is doing? Is the 4k rpm lean-rich point the cross over from open loop to closed loop? Also, what other strange things happen to our motors at different rpm points? When do the different solenoids in the intake manifold actuate at?
Also, I'm not sure if any ecu would work, there are two different products made by split second and each do different things. If this is a timing issue I would need to get the SSFTC.
 
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This is not totally a timing issue, though it is partially. Yes, that 4k RPM spot is the switchover from closed to open loop. Other strange things shouldn't happen at a given RPM. I'm not sure when the solenoids activate for the IM. Here's what you should do: Get your ECU re-flashed at the dealer, then buy a SS-AFC and lean that mixture out.
 
HondaEat-R said:
This is not totally a timing issue, though it is partially. Yes, that 4k RPM spot is the switchover from closed to open loop. Other strange things shouldn't happen at a given RPM. I'm not sure when the solenoids activate for the IM. Here's what you should do: Get your ECU re-flashed at the dealer, then buy a SS-AFC and lean that mixture out.
Click to expand...

Will the SSAFC also fix the LEAN numbers during closed loop (before 4k rpm)?
 
What also bothers me about the chart, is how much the AFR is swinging around before 4k rpm. Its going from 14-16 too often. Is this also normal for a MSP ECU?
 
i get the same afr numbers on my wideband everytime i wot right now since im on stock tune for the time being. like stated before u will need some sort of piggyback if u want to change the fuel trim. dont worry too much about the actuators opening the butterflies in the manny, as a matter of fact u should just remove them.
 
Personally, I think the FMIC is why your'e running in the 14s under 3800rpm.

Opinions aside, the jumping up and down is the result of the ecu trying to correct the AFRs.

From the chart, *technically* you are leaking, as every dip in AFR is associated with a dip in PSI. However, it isn't a leak to worry about (meaning the WGA is working as perfectly as it can in a real world scenario). What is happening is that the WG is varying in its "openess". It's a very minute physical change, as evident by a max change in pressure of about .2 -.3 psi (from your chart) from each local min to local max.

As njaremka said, it looks like a pretty normal oem ecu tune: Pig Rich. Perfect stoich is 14.7:1, the general consensus is you should be at 12.9:1 to allow for local spikes, which will also put your mind at ease about any given rpm... merely local spikes.

btw, I lol'd when I read that the engine started making a different noise around 4k.... I kept thinking, "yeah, that's the turbo".
 
I ordered the SS AFC v2 from Protege Garage yesterday. Hopefully I'll get it installed this weekend. Anyone have tips?
 
Only tip i can think of is to have someone experienced tune it for you.

Have fun with it!
 
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I have installed the SSAFC and interfaced it to my laptop. Looking over the included map, it contains no fuel change for RPM less than 4k RPM. This is why I bought the product, to fix the lean before 4k rpm. Does anyone know why this isn't addressed with the SSAFC? Since I do not have my own wide band I cannot tune this myself. I thought the lean (14-16 AFR) at 8PSI before 4k RPM (see chart on first post) is a problem with all MSPs. Is there something wrong with mine? Please give some suggestions. I would like the AFRs before 4k to be around 13.
Thanks
 
Cuz you can't tune while the ECU is operating in closed loop. Not with a signal modifier like the SS AFC at least.

Only suggestion I have for the SS AFC is to make sure to solder the connections. And make sure to get a good vacuum sourced for the MAP sensor inside it, somewhere right off the intake manifold is preferred. Tuning is cake though, but a wideband is definitely essential.. it would probably be a worth investment if you plan on owning the car for a while.
 
KrayzieFox said:
Cuz you can't tune while the ECU is operating in closed loop. Not with a signal modifier like the SS AFC at least.
Click to expand...

Are you sure about this? I was told by the company that makes the psc1, that it does adjust fuel trim during closed loop. Anyone else know if the ss afc can adjust fuel when the ecu is in closed loop (before 4k rpm)?
 
codex said:
Are you sure about this? I was told by the company that makes the psc1, that it does adjust fuel trim during closed loop. Anyone else know if the ss afc can adjust fuel when the ecu is in closed loop (before 4k rpm)?
Click to expand...

Straight from Split Second's tuning guide document.

http://www.gadgetonline.com/U-Tune.pdf

"Closed Loop Mode:

The manufacturer programs the stock ECU with a lookup table that it uses to
determine how much fuel to inject into the engine. It uses engine RPM, throttle
position, the amount of air by weight, the temperature of the air entering the
engine, and the engine coolant temperature to determine how much fuel by
weight to inject into the engine. This initial amount of fuel is fine-tuned based on
the reading from the oxygen sensor. The adjustment it makes to the standard
lookup table is called fuel “trimming”. When the ECU is making these fine
adjustments to the fuel mixture using feedback from the oxygen sensor, the ECU
is operating in CLOSED LOOP mode.

When the ECU is operating in CLOSED LOOP mode you do not have control
over the mixture with a programmable calibrator. If you try to increase the MAF
signal to make it run richer, the ECU will just trim the fuel back out to keep the
mixture near the preset 14.7:1 air fuel ratio by weight. It is important that this is
clearly understood. For the most part you cannot change the mixture while the
ECU is operating in CLOSED LOOP mode. If you try the ECU will resist keeping
the mixture where it thinks it is supposed to be. There is a limit to how much
control authority the ECU has to adjust the mixture. If the maximum fuel trim
limit is exceeded and the ECU looses control of the mixture in CLOSED LOOP
mode it will set a check engine light. You must work with the ECU when tuning
CLOSED LOOP and not against it. The ECU will win every time.

What you can control with a programmable calibrator in CLOSED LOOP is the
amount of trimming the ECU has to do. You will enjoy the best drivability when
the fuel trims are minimized throughout the CLOSED LOOP region."
 
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