injector duty cycle help

mike93hatch · Post by **mike93hatch** » Mon Jan 14, 2008 8:21 pm

why is it that smanager is has always said ive been running 114% injector duty cycle? if that was true, wouldnt i be leaning out? 11.8:1 afr at 8500rpms.

how can i fix this?

Post by **Hondata** » Tue Jan 15, 2008 10:03 am

It should not read over 100% - it is a bug. However, if you're getting to 100%, it means that you're going to start running lean. You should consider bigger injectors or raising the fuel pressure (if the fuel pressure is not too high to begin with).

mike93hatch · Post by **mike93hatch** » Tue Jan 15, 2008 4:22 pm

Hondata wrote:It should not read over 100% - it is a bug. However, if you're getting to 100%, it means that you're going to start running lean. You should consider bigger injectors or raising the fuel pressure (if the fuel pressure is not too high to begin with).

it sure does, you want the log?

it has been reading over 100% duty cycle for over a year now..

it has never ran lean. so what now?

i did raise the fuel pressure to 49psi and adjusted the fuel maps so afr was the same 11.8:1 and the duty cycle just went up more. something is wrong or there is a setting somewhere im not doing right.

Post by **Spunkster** » Wed Jan 16, 2008 10:44 am

This is usually caused by someone making large changes to the fuel tables without properly adjusting the fuel multiplier first.

mike93hatch · Post by **mike93hatch** » Wed Jan 16, 2008 3:54 pm

Spunkster wrote:This is usually caused by someone making large changes to the fuel tables without properly adjusting the fuel multiplier first.

yea i did make some changes to the fuel since my new intake manifold wanted alot more.. what else do i need to change? where is the fuel multiplier and what does it do?

but it read over 100% before i made these changes as well.. i dont know..

Post by **Spunkster** » Wed Jan 16, 2008 4:54 pm

Look at the Fuel trim tab

mike93hatch · Post by **mike93hatch** » Wed Jan 16, 2008 8:06 pm

i dont fully understand the whole fuel trim tab... how are you suppose to know what it should be. and when you do stuff to that does it take fuel out of the whole map? and then i would need to retune again? just get to get the duty cycle working right? im not leaning out and never have over the whole year this engine setup has been running so i may just say screw it.

Post by **Spunkster** » Thu Jan 17, 2008 10:28 am

When you first start to create a calibration you use the injector size setting to get as close as you can to the right AF, then if any small changes are needed you chane the overall fuel trim, then to fine tune the individual areas you use the tables.