Problems with Tuning Fuel Maps
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Problems with Tuning Fuel Maps
Hallo,
i have a strange problem when tuning my fuel maps for my car.
when i try to tune it to the correct AF Ratio under boost (12.5:1 is my goal) for full throttle this is possible.
Procedure is the following: taking a long straight road, putting the car in 3rd gear and floor it from 2000rpm to 7000rpm and look at the AF Ratio... then i correct the specific columns where he runs to lean or to rich to get my 12.5:1 ... until now everything works fine.
yesterday i realized when i drive with part throttle (3/4 throttle pos i.e.) on the hightway in 4th or 5th gear and in an rpm band where it is possible to build full boost (8psi) with this throtle position. The car leans out extreamly (nearly 14:1, sometimes 15:1 or 15.8:1 UNDER BOOST!!!) when i retry this with full throttle i have an exact mixture of 12.5:1
What can that be???? did i make anything wrong?
i think the ecu make something like a full throttle enrichment... this can explain this phenomen, but how do i have to tune my fuelmap then???
Thanks
Malte.
i have a strange problem when tuning my fuel maps for my car.
when i try to tune it to the correct AF Ratio under boost (12.5:1 is my goal) for full throttle this is possible.
Procedure is the following: taking a long straight road, putting the car in 3rd gear and floor it from 2000rpm to 7000rpm and look at the AF Ratio... then i correct the specific columns where he runs to lean or to rich to get my 12.5:1 ... until now everything works fine.
yesterday i realized when i drive with part throttle (3/4 throttle pos i.e.) on the hightway in 4th or 5th gear and in an rpm band where it is possible to build full boost (8psi) with this throtle position. The car leans out extreamly (nearly 14:1, sometimes 15:1 or 15.8:1 UNDER BOOST!!!) when i retry this with full throttle i have an exact mixture of 12.5:1
What can that be???? did i make anything wrong?
i think the ecu make something like a full throttle enrichment... this can explain this phenomen, but how do i have to tune my fuelmap then???
Thanks
Malte.
#2
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Re: Problems with Tuning Fuel Maps (mrx)
I think the easiest solution is to change your driving style. If you are in 5th gear and boosting, unintentionally, just downshift and you will be back in vac., hopefully.
Otherwise, you could turn off closed-loop and get horrible mileage, but avoid this completely. (second easiest solution, but pretty ghetto).
What are you using to tune the car? If you are using an AFC, I think you're limited to the previous options, but anything else depends on what you are running and thus can change.
Otherwise, you could turn off closed-loop and get horrible mileage, but avoid this completely. (second easiest solution, but pretty ghetto).
What are you using to tune the car? If you are using an AFC, I think you're limited to the previous options, but anything else depends on what you are running and thus can change.
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Re: Problems with Tuning Fuel Maps (ion_four)
I think change the driving style to avoid bad fuelmaps is more ghetto style then anything else...
i don't know your cars behavior but if i drive on the highway at 5krpm i can build boost with about 1/4 of throttle... thats no magic thing... so it would be very hard to avoid this... becuase it is also possible in 5th gear ;-) and where do i have to shitft then???
at the moment closed loop is disabled for tuning... so closed loop is not the causing problem.
i'am tuning via a free programmable DIY solution... from its functionality like the old PW0 hondata systems.
ECU is also a OBD0 PW0
Greets
Malte.
i don't know your cars behavior but if i drive on the highway at 5krpm i can build boost with about 1/4 of throttle... thats no magic thing... so it would be very hard to avoid this... becuase it is also possible in 5th gear ;-) and where do i have to shitft then???
at the moment closed loop is disabled for tuning... so closed loop is not the causing problem.
i'am tuning via a free programmable DIY solution... from its functionality like the old PW0 hondata systems.
ECU is also a OBD0 PW0
Greets
Malte.
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Re: Problems with Tuning Fuel Maps (mrx)
Hi,
here i have two pictures of my current fuel map setting (lowcam and below highcam)
i think they are more or less smooth so i'am very confused because especialy under pressure values between 1000-1600mbar the mixture flickers between 14-11:1 sometimes it is leaner sometimes it is richer... so i don't know in which direction i have to tune...
PS: i use a wideband!
And here the highcam:
maybe someone can give me an advise...
the numbers on the right side are map values in mbar and the values on the Y Axis of the diagram are the injector open time (same like hondata used them in thair rom editor)
Greets
Malte.
here i have two pictures of my current fuel map setting (lowcam and below highcam)
i think they are more or less smooth so i'am very confused because especialy under pressure values between 1000-1600mbar the mixture flickers between 14-11:1 sometimes it is leaner sometimes it is richer... so i don't know in which direction i have to tune...
PS: i use a wideband!
And here the highcam:
maybe someone can give me an advise...
the numbers on the right side are map values in mbar and the values on the Y Axis of the diagram are the injector open time (same like hondata used them in thair rom editor)
Greets
Malte.
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Re: Problems with Tuning Fuel Maps (Swags04)
Hallo,
i have a small update, i guess my errors come from the fast throttle enrichment that the ecu does when you quickly open the throttle.
i made a testdrive a few min. ago and it seems to me that when i make a full throttle run then my mixture is ok, becuase of the throttle enrichment, if i make the same run with i.e. 1/2 throttle then the ecu don't make an enrichment because i don't open the throttle quick and wide enough.
so i think my maps are generaly to lean in this area.
But there i one last question, if the throttle enrichment makes a difference from 15:1 (without) and 13:1 (with enrichment) what is my mixture when i tune my maps for 12,5:1 without enrichment? then i can expect 10:1 or more or what?
does anyone realized this behavior on other hondas during tuning? or do you tune your cars only for full throttle? and ignore the mixture when dirivng with part throttle?
Greets
Malte.
i have a small update, i guess my errors come from the fast throttle enrichment that the ecu does when you quickly open the throttle.
i made a testdrive a few min. ago and it seems to me that when i make a full throttle run then my mixture is ok, becuase of the throttle enrichment, if i make the same run with i.e. 1/2 throttle then the ecu don't make an enrichment because i don't open the throttle quick and wide enough.
so i think my maps are generaly to lean in this area.
But there i one last question, if the throttle enrichment makes a difference from 15:1 (without) and 13:1 (with enrichment) what is my mixture when i tune my maps for 12,5:1 without enrichment? then i can expect 10:1 or more or what?
does anyone realized this behavior on other hondas during tuning? or do you tune your cars only for full throttle? and ignore the mixture when dirivng with part throttle?
Greets
Malte.
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