Affects of C6101

Working on a 5.3 LM7 (flexfuel) with an LSA supercharge installed in a 1971 chevelle. Getting the motor going and trying to get it dialed in. Before the blower it started and ran great, as it was all stock. However, with the blower it requires different injectors, so i installed 1000cc FIC injectors which fit the LSA. I have updated all the tables for the values of the larger injectors. However, it runs extremely rich until it warms up enough for close loop and then has about 18% ltft.

The other issue was when I gave it throttle it would go into limp mode and throw code P1514. I believe it was because of table C6101 ETC Predicted Airflow. In the COS tutorial it mentions increasing the values of this table so it won't cause issues, so I increased the table by 50%.

My question is why is it running so rich? I have backed off the VE table to get it close, but I believe with the correct injector info it should run and idle just like stock. Even though it has a blower on it, the motor is completely stock so I'd assume the stock VE table should be relatively close. Does increasing the values of C6101 have an affect on calculated airflow since I have switch to a SD tune? Or is there some other issue, or something i am missing? (assuming it is the fuel injectors?)

I have attached my tune.

Please post some log files.

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Originally Posted by joecar

Please post some log files.

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Here is quick lock of starting up at idle. you can see it extremely rich until the LTFT kicks in.

Are you running MAF...?

IFR table is wrong.

Is your injector supply (fuel system) return-less (single line, with FPR at fuel pump) or return (two lines, with FPR at rail)...?

Quote:

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Originally Posted by joecar

IFR table is wrong.

Is your injector supply (fuel system) return-less (single line, with FPR at fuel pump) or return (two lines, with FPR at rail)...?

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It is running a return-less constant fuel pressure regulator back at the tank (corvette filter/regulator).

I am also running with out a MAF.

The values in that table are what I received from the fuel injector supplier, what is incorrect about them? If you like I have the excel file for the information on these injectors. I could be miss interpreting or reading incorrectly. I tried to attach it but I get an error "invalid file" type, it is a .xlsx spreadsheet.

Your IFR table B4001 has a flat and then a linear slope (see pic from your .ctz):

Attachment 23604

It should look like this (note that it appears linear but is actually curved slightly) (and of course, scaled up to match your injectors' flow rate):

Attachment 23605



IFR is supposed to go as squareroot of pressure (more detailed info here: Calculating-Injector-Flow-rate).

With a dog-leg shaped IFR table, it will be difficult/impossible to correct the VE table for all driving conditions (i.e. maybe doable for WOT dragstrip use only, but not PT cruising and not idling).

You likely need to adjust min transient pulsewidth which is not defined by EFILive. The table is B9021

You may be able to find someone to make you a CAX file to define the table so you can lower the IPW at idle through the VE table.

You need to log calculated airflow and determine if and where you are exceeding the values defined in C6101.