Can someone help me understand DFCO?
11-16-2010, 09:14 PM
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Can someone help me understand DFCO? Hey all, I understand what DFCO is and I know my car is not enabling it after the cam swap. When I shift gears (let off the gas) the exhaust pops, and when I'm in neutral or have the clutch in and I'm braking to a stop, the RPMs don't drop very quickly (it'll stay around 1500 until the car comes to a complete stop, then it'll drop to idle).
I know there is some other tuning involved, but I'm doing one thing at a time, heh.
So anyway: (this is all in HPTuners)
1) What does Enable RPM vs Gear mean? I know the logic but not the on/off. There's an entry and an exit tab, does the rpm need to be above or below each of those things to turn DFCO on? It's unclear as to what it needs to do to enter/exit.
2) Same question for MAP enable. Does it need to be above/below to turn on/off? Explain it as specifically as you can, like I'm a moron. heh.
3) Startup modifiers (is this important?)
4)Cutoff RPM tab
Thank you very much for any help you can provide, you guys are the best.
I know there is some other tuning involved, but I'm doing one thing at a time, heh.
So anyway: (this is all in HPTuners)
1) What does Enable RPM vs Gear mean? I know the logic but not the on/off. There's an entry and an exit tab, does the rpm need to be above or below each of those things to turn DFCO on? It's unclear as to what it needs to do to enter/exit.
2) Same question for MAP enable. Does it need to be above/below to turn on/off? Explain it as specifically as you can, like I'm a moron. heh.
3) Startup modifiers (is this important?)
4)Cutoff RPM tab
Thank you very much for any help you can provide, you guys are the best.
11-17-2010, 08:30 PM
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1) For the entry tab - The rpm needs to be above that value for the engine to enter DFCO. For the exit tab - the engine will exit DFCO when that rpm is reached. In HPTuners it says that the rpm must exceed the value, this is for both the entry and exit tabs.
2) Same applies for the MAP enable/disable.
I'll answer 4 first cause 3 sort of depends on it.
4) The cutoff rpm tabs control the rpm limits if the gear is in park/neutral or if there is a problem with the Vehicle Speed Sensor. They also control the rpm limit depending on which gear the transmission is in. That is is the Normal table. The second table controls based on the electronic throttle. Don't worry about that one.
Now to the start-up modifiers.
3) The start-up modifier rpm table determines the rpm limit based on engine temperature. The delay table sets a time limit for using the other modifier table. It's values are different depending on engine temperature as well. After that time limit has expired the other rpm limits take affect.
I hope I answered your questions. I know I'm not good at explaining things well.
2) Same applies for the MAP enable/disable.
I'll answer 4 first cause 3 sort of depends on it.
4) The cutoff rpm tabs control the rpm limits if the gear is in park/neutral or if there is a problem with the Vehicle Speed Sensor. They also control the rpm limit depending on which gear the transmission is in. That is is the Normal table. The second table controls based on the electronic throttle. Don't worry about that one.
Now to the start-up modifiers.
3) The start-up modifier rpm table determines the rpm limit based on engine temperature. The delay table sets a time limit for using the other modifier table. It's values are different depending on engine temperature as well. After that time limit has expired the other rpm limits take affect.
I hope I answered your questions. I know I'm not good at explaining things well.
