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View Full Version : How do you tune in open loop???



WiseGuyZ06
May 19th, 2007, 01:44 AM
like the title says....

thanks...

SSpdDmon
May 19th, 2007, 02:32 AM
First, some helpful tips since you sound new to this: Open the tuning tool and hit Alt+Enter. Change the fueling display values to AFR. That way, you don't have to worry about dealing with EQ or Lambda. Then, download your tune out of your car. If it's not a stock tune, download a copy of a stock tune for your car from www.holdencrazy.com (http://www.holdencrazy.com) for reference. You can compare your current tune with another tune (e.g. the stock one) by hitting Ctrl+F11 as long as they have the same operating system. Ctrl+4 will show you the current file and Ctrl+5 will show you the alternate/comparison file.

You force your car into open loop by setting the closed loop temp enable table to its maximum across the board. This disables STFTs and closed loop. You should also turn off LTFTs and DFCO (set temp enable to it's max). Set your Commanded Fueling in Open Loop table to a 14.63 AFR from 158*F on up and set your PE table appropriately (e.g. a 12.5:1 AFR is a good target for NA cars). You might want to drop the PE TPS enable table a little too.

Now you're in open loop. The MAF is still active and influencing fueling. If you want to go to speed density, you need to disable the MAF under Engine Diagnostics. Set the high fail frequency to 1 and the fail limit to 1 (C2901 and C2903). This will trigger an SES light. You can turn that off in the first few rows of the DTC MIL section. In speed density, the timing scaler reverts the PCM to the low octane timing table. You need to copy the values in the high octane table to the low octane table.

Now, you're in open loop speed density (no MAF). Depending on how heavily modified your car is, you want to go to the VE table and change a few cells. If you're just a bolt-ons car, you should probably increase the VE 5% from 40~105kPa and 2000~8000 rpms. That'll help keep you from running too lean the first time around. Other setups will require different changes (e.g. cammed cars need to remove fuel from the stock VE below 1600rpms in order to idle....however, they need more than 5% above 2400rpms).

Those are the firsts step in getting there. I just realized all of this is in the tutorial along with the remaining steps. So, check that out... ;)

WiseGuyZ06
May 19th, 2007, 11:38 AM
hey thats cool a big help.... do u prefer SD or OL???

SSpdDmon
May 19th, 2007, 11:55 AM
hey thats cool a big help.... do u prefer SD or OL???
Well, I'm currently running a speed density open loop tune. Ideally, I'd like to get my car back to closed loop MAF operation. But, the cam doesn't exactly play nice with the PCM. If I can get the MAF calibrated decently and without issue, I'll probably end up running an open loop MAF tune.

WiseGuyZ06
May 19th, 2007, 12:01 PM
So i might just try OL... IT LOOKS EASY TO DO... how do i change my afr, under the pe table???

is there anything else i should know...

WiseGuyZ06
May 20th, 2007, 03:14 PM
This guy know what he's talking about.... he called me over the phone gave me a quick rundown and I learned alot..... great help here fellas

SSpdDmon
May 20th, 2007, 03:26 PM
This guy know what he's talking about.... he called me over the phone gave me a quick rundown and I learned alot..... great help here fellas
Glad I could help... :)

WiseGuyZ06
May 20th, 2007, 06:25 PM
u da man!!!!!!!!!!!!!!!! big help