Open loop problems!
 

I have been having trouble with open loop come on too early in the rev range!!

So this is what I've done so far.

I have a WRX 04 plate with a TD5-20g turbo. I noticed though my data logging that my g/s has increased by 4% though out the closed loop section in my maf table. This makes sense "Bigger turbo wants more air." I have installed the decapped injectors rated to 840cc which in ecuflash I put 820.08 in the flow rate table. Did a closed loop run & noticed in the fuel trims -25%, & my open loop came on about 2100 rpm @ 2.48v. So upped the flow rate table to 1025.02, this caused my ltft to hit -.68%, my open loop still came on about 2100 rpm @ 2.48v.

So then I went back & punched in 820.08 flow rate, but this time reduced to maf table by 25%. Went out & did the run again. This time my open loop came on at 3100 rpm @ 2.84v with +2.05 ltft.

So my delema is
1: Is there another way to get open loop to come in later up the rev range & maf v, so I can up the maf g/s back to what the car wants to be?

Get a proper mapper.

there are several tables in the map for closed loop/open loop transition, just monkeying around with things without being sure what they do will almost certainly end in disaster for you.

As Stu says get a proper map done or read a lot more on what's happening with each of the tables before making changes.


For what it's worth your changes to the flow rate are most likely influencing the the base pluse width transition value - but you don't mention what ECU your using so you could also have throttle and RPM based compensations working in the background also. The flow rate should match fairly closely with what your injectors were flow tested as - if you simply decapped them and fired them back in without testing then you can't even be sure that all 4 flow the same amount so another potential disaster lurking for you.

Never had to messed with the closed/open loop transition. It also doesn't bother me as long as the AFR is correct. Who cares whether its running closed of open loop as long as the AFR is where you want it. Closed loop is only going to help an MOT emissions test with keeping things tighter.

Also as long as the AFR out pipe is where you want it MAF scaling doesn't need changing, if you can live with your AFR tables not matching actual AFR.
The MAF scaling only needs tweaking if you desire to have AFR from the car close to the AFR tables and within the +/-14% fuel trim/correction to prevent a CEL.

You can also disable the fuel trim so closed loop trim is not applied to open loop. This is handy for vehicles who can over time trim a little too much in closed loop for unknown reasons and end up running a little leaner then when you last saw it/left it.