Commanded AFR in PE mode question
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From: Lexington, KY
Commanded AFR in PE mode question I am working on PE mode for my 99 Z28, which has been migrated to a 02 operating system. I'm using EFI Live. It's a heads/cam/intake/headers car with 30 lb injectors, which I have rescaled the IFR table for. I have done AutoVE a few times and I think my VE table is pretty close. I made a few runs this morning in SD closed loop, and commanded AFR (and actual) is following B3618 as it should (12.75 AFR), until 5600 rpm. Then commanded (and actual) drops to 11.9. About the time it hits 2nd gear, commanded drops to 11.7 and stays there until I let off.
Why does it not stay at 12.75 as I have it set in B3618? Coolant temp was 180 degrees, which puts B3617 (PE modifier based on coolant temp) in a range of 0 adjustment. B3614 (PE modifier based on intake temp) is set to 0 across the board. Is it possible it went into piston protection mode and is using B3659 (commanded fuel when in piston protection mode)? The only possibility I can see here is that it triggered B3652 (piston protection MAF limit), which I have not changed but was not logging at the time, however the MAF was turned off and unplugged.
Please help, thanks.
Why does it not stay at 12.75 as I have it set in B3618? Coolant temp was 180 degrees, which puts B3617 (PE modifier based on coolant temp) in a range of 0 adjustment. B3614 (PE modifier based on intake temp) is set to 0 across the board. Is it possible it went into piston protection mode and is using B3659 (commanded fuel when in piston protection mode)? The only possibility I can see here is that it triggered B3652 (piston protection MAF limit), which I have not changed but was not logging at the time, however the MAF was turned off and unplugged.
Please help, thanks.
Thread Starter
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Joined: Feb 2004
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From: Lexington, KY
Cat protection (B0701) is turned off. I haven't adjusted any of the other cat protection values. Do I need to?
Steve: my PE modifier based on rpm table (B3618) is set to 12.75 AFR across the board. I plan on tweaking this at the track but it won't do any good if it's not following it. Do I need to adjust PE settings elsewhere?
Steve: my PE modifier based on rpm table (B3618) is set to 12.75 AFR across the board. I plan on tweaking this at the track but it won't do any good if it's not following it. Do I need to adjust PE settings elsewhere?
Interested to see what you find out. My car is mostly stock (lid/catback) but I have EFI Live with a few tweaks and out of curiousity I logged it a bit last night. Mine did the same thing, ECT was 183 degrees, and rolling into it in 2nd gear it commanded what my table had until ~5400 RPM when it dropped to 11.70 just like yours.
Thread Starter
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From: Lexington, KY
I think torque limiting is just during a shift, not postive though, or what adjustments it makes. I have removed alot of it though. I think for some reason it's using the piston protection mode table, as it commands 11.70 which is exactly where it goes to. If the storms move out I'm taking it to the track tonight so hopefully I'll get a chance to experiment with it. If nothing else I can try changing the piston protection mode table and see if that corrects it. I did have my maf unplugged, so maybe it defaults to this if it's not getting a signal?
Maybe someone who knows more about it will chime in.
Maybe someone who knows more about it will chime in.
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Verdad Gallardo Thread Starter
TECH Fanatic
Joined: Feb 2004
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From: Lexington, KY
Well that is interesting. I'm not sure what is going on. I'm going to try copying the PE modifier based on RPM table to the piston protection mode table and see what happens. It may be defaulting to this table for another reason. I can't see what else it could be, but I'm still learning my way around this.
Well that is interesting. I'm not sure what is going on. I'm going to try copying the PE modifier based on RPM table to the piston protection mode table and see what happens. It may be defaulting to this table for another reason. I can't see what else it could be, but I'm still learning my way around this.
Hopefully it will move on through. I looked at my tables last night and 11.70 was actually the value in my "cat protection mode" table, whereas the engine protection was something like 12.9. Don't know if that helps at all, you probably already looked at that table too.
