little/slow throttle AE
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Car: 1990 Corvette
Engine: 415
Transmission: six speed
Axle/Gears: Dana44 3.73
little/slow throttle AE
hi all
i have tried a lot to fight this problem, now i think its time to ask...
when i open the throttle very slowly and not very much, about 2-5% from a standstill, or in low load condition, i notice the AFR goes up to 16-17, then settles back to around 14.7
the intake is a single plane EFI, 58mm TB , $8D
the car drives good, but i think, here is still some more driveability to gather
can you tell me, at which AE tables i should look, would be great!
thank you
i have tried a lot to fight this problem, now i think its time to ask...
when i open the throttle very slowly and not very much, about 2-5% from a standstill, or in low load condition, i notice the AFR goes up to 16-17, then settles back to around 14.7
the intake is a single plane EFI, 58mm TB , $8D
the car drives good, but i think, here is still some more driveability to gather
can you tell me, at which AE tables i should look, would be great!
thank you
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Re: little/slow throttle AE
This is a difficult area to tune. The PW difference between too little AE and too much AE at low throttle changes is small.
One way around this is to put a little more into the VE table. This is basically hiding AE in the VE table. Do this in areas that you rarely ever stay in, and of course in the area that is traveled as the throttle is opened.
On port injection I go by the INT in these cases. It is best to have the INT rise a little. Having too much AE and as a result a falling INT leads to a lean sag as the AE runs out.
RBob.
One way around this is to put a little more into the VE table. This is basically hiding AE in the VE table. Do this in areas that you rarely ever stay in, and of course in the area that is traveled as the throttle is opened.
On port injection I go by the INT in these cases. It is best to have the INT rise a little. Having too much AE and as a result a falling INT leads to a lean sag as the AE runs out.
RBob.
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Re: little/slow throttle AE
Originally Posted by 396V8
when i open the throttle very slowly and not very much, about 2-5% from a standstill, or in low load condition, i notice the AFR goes up to 16-17, then settles back to around 14.7...
#4
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Car: 1990 Corvette
Engine: 415
Transmission: six speed
Axle/Gears: Dana44 3.73
Re: little/slow throttle AE
Bob is of course right, as it sounds more like it is in your VE table. If your running a NB O2 sensor then your air/fuel readings are normal. It will swing to maintain an average, as I too will see as low as 300mv with a NB sensor when gradually increasing the throttle. It's normal. If you patched a wideband into $8D, and your readings are still low, then like Bob said, increase your fuel in that VE area...
i run a WbO2, but just for measuring, the ECM relies still on the NbO2
i see this behavior on the WbO2, if i dont have one, im pretty sure, i wouldnt notice..
ist not easy of corse for the ecm to identify this area..Little to no map Change, and the throttle is moved so slightly that it seems, theres no Delta for the ecm
will try to adjust the VE tables, i will Keep you updated
thank you
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