Leaning out after 4500rpm

[biondos1]

whats up guys
i installed the ssafc and tweaked the kelly2 map
AFR are 11.8-12.1 to about 4500 and then moves in the mid 12's. by 6000rpm its at 13.2 afr
but on the map i added fuel and it made no difference
is this is a symptom of a failing fuel pump.
as preventative maintenance i ordered a walbro 255 but could there be another issue im not seeing here. no cel lights and car pulls strong up to 4500rpm then you feel like its starving for fuel


mods:
ssafc
smic
j-pipe back exhaust / stock muffler
injen intake / relocated maf
wideband o2
mbc @ 9-10psi
150,000 miles
new o2 sensors

thanks

 

[Protege03ak46]

Bad tps or bad interpretation of tps signal to SSAFC.

 

[biondos1]

thanks
i found this post
http://www.mazdas247.com/forum/showthread.php?123792909-how-to-adjust-throttle-position-sensor

but if this is my issue how do i adjust the tps?

 

[biondos1]

checked voltage at the tps and it seems like its okay. with key in the ignition the tps is getting 4.98 volts output is .55 volts with throttle closed. when i press the throttle the output voltage goes up to 4.24v.

 

[dmention7]

I had a similar problem when I first installed my SSAFC. Car would pull great and perfect AFRs up through about 4k rpms, then it would bog down and AFRs went through the roof. The problem was in the Options / System Settings menu of the R4 software, the "Over RPM" value was too high. Check that yours is set around 3500 rpm.

 

[Geezer000]

I had a similar problem when I first installed my SSAFC. Car would pull great and perfect AFRs up through about 4k rpms, then it would bog down and AFRs went through the roof. The problem was in the Options / System Settings menu of the R4 software, the "Over RPM" value was too high. Check that yours is set around 3500 rpm.

What does that do?

 

[dmention7]

I'm not positive on the details, but I think it has to do with when the O2 clamp kicks in. So above that rpm (and above the "Over Pressure" value), the O2 voltage is clamped to keep the car from trying to maintain N/A-like AFRs until it goes into open loop. Maybe someone else can chime in with more info... I'm just going off some bits of what I was told and what I read. Unfortunately, I've never seen any documentation from SplitSecond on exactly what many of those parameters do.

But basically, before I made that change, I could modify the cells in the 3500-4500 rpm range to whatever the heck I wanted, but it would always go stupid lean.

 

[biondos1]

thats exactly it. i changed my value all the way down to 9.0 and it didnt affect my afrs. thanks ill check this when i get home.

 

[dmention7]

Hold up.... just to check, you know that the values in the cells are not a target AFR, correct? They represent the amount the MAFS voltage is modified, with 10 being no modification. If you lower the cell value to 9, you are decreasing the MAFS voltage that the ECU sees--in effect telling it that there's less air entering the motor and to add less fuel. That's going to cause you to lean out pretty good (especially lowering the cell value by a whole point). If you want to add fuel, the cell values should be increased.

 

[biondos1]

hmm...i guess your right
stock the car is running extremely rich so thats why we lower the value. i havent had a chance to really check yet but the thing is that when i uploaded the kelly2 map the same thing was happening and the values were 9.7. i have to check the over rpm thing, and then i play with the values some more.

 

[biondos1]

yup the kelly2 was leaner up top because of him having an exhaust cutout. i bumped up the values to 9.5 and runs perfect along with changing the over rpm value. thanks guys

 

[jbrewer4639]

good info