AEM v1 30-1050u ems. Notice when I quickly open the 74mm Throttle Body to about 30% it hesitates. The engine was pig rich 11.5afr on pump 91, Coolant Temp 100F and the temp that day was a cool 60F.
I'm wondering if it could be due to "Acceleration Fuel". I don't fully understand how the Acceleration/Decel Fuel works yeat. But, i'm now working on figuring out the functions there.
The way it hesitates seems like it was a lack of Fuel when the Throttle was quickly blipped open IMO.

This video was from last year, the car is still completly tore down and i'll be starting to put it back togather later this month. So I can't really run tests or anything, I just would like some opinions on what it could have been

 

Fuel Tip-in?

 

It definitely seems like an acceleration fuel problem, but it's hard to say without seeing your calibration or any datalogs.

If you recorded any logs of this happening, did you notice AFR get really lean or really rich as you tipped in?

Can you post a screen grab of your accel fuel template?

 

Throttle Accel Template


Load Accel Template


These are from last years Calibration, using Startup Calibration named; 1050 Turbo 440. V1.19 I modified some other things of course. But, never touched either of these.
Below i'v also attached my entire Calibration if you feel like browsing through it.
If you guys need anymore info on the setup etc... Just let me know.

I saved this Cal to my email before doing a System Restore on my loopy laptop.
I was actually logging at this time however did not save the logs.
I did not notice it go Lean on the log. I was doing PC Log on slow update rates at this time. I don't think that Throttle blip affected the o2 Sensor enough to pic up that instance.

 

Drop your Accel dTPS trigger to 3.
Increase Pump Sustain to ~25%
Idle car - make sure vacuum fluctuations don't trigger accel fuel at idle. If not - good to go.

Also, is this a boost comp or a 3D tune? Since accel fuel is multiplied from the primary fuel map, different accel strategies are necessary.

Completely disregard load based accel with a S1 box. Forget it exists.

 

Yea, I was already planning on this. I was only gonna go to 7 on the trigger and 14 on Sustain(I didn't know how far I could reasonably go on these options). On the Accel TP Sensitivty I was also considering dropping it to 80%.

Are you talking about vacuum leaks? I don't see why the vacuum would fluctuat if idle was stable and theres no vacuum leaks.

At the time of the Video no. I am planning on trying to use the Boost Target Comp yes. However that shouldn't have any Fueling effects in the Vacuum range.

This is good to know. Does it just not work right? And, should I leave the current tables in dmap as is or should I zero them all out or anything?
Thanks for the help, definatly picking up some useful information.

 

You'd want to increase Sensitivity to (in theory) increase response. (see below)

Nope, not talking about vacuum leaks. I presume you're dealing with a properly running engine. This varies with the engine, throttle body, and TPS being used, but in many cases at idle, your TPS will not read a rock-solid 0%. Vacuum + vibrations can cause slight TPS movements. Since I'm telling you to decrease your accel trigger to an extremely low TPS threshold, we need to make sure slight TPS fluctuations at ilde don't trigger accel fuel. That's all.

Boost Comp will most definitely affect your fueling in vacuum. If mathematically correct, the boost comp table should be pulling 100% at 30" and adding 100% for every 14.7 psi. This is what allows your primary fuel table to be "flat" thus adding tons of adjustment range and resolution.

I don't know AEM's official position on S1 load based accel, but I don't know of anyone, anywhere, using it on anything. I've tried it in conjunction with TPS based enrichment and independantly - never consistent.

 

My bad I was confused with "Boost Fuel Correct", or maybe were both confused. As this table sounds like control over what your describing above. This is basically how i'd try to set this up.


I haven't fully figured out "Boost Comp" from my knull understanding it helps the Boost Target so the Feedback has to do less work to stay on Target when setup correctly?
For now i'm going for a Boost by gear setup. So with my understanding of Boost Comp I don't think it would be necessary for me to use.

I get what your saying about the Resting %TPS. Mine seemed to stay at %0, so I agree with setting the Accel dTPS Trigger to 3.

I only noticed this happen once. The car had been started and idled like 3 times before this Hesitation instance and I had probably ran it for no more than 10mins each time, at 11.0afr and #9 heat range(cold plugs). I honestly think at this point the Plugs were just fouled out. I started pulling the motor apart the next day for another makeover and when I pulled the Plugs they were Brand new and Black as night. Fouled plugs were probably the problem here. Wouldn't you guys agree?