groovezog Posted February 7, 2021 Report Share Posted February 7, 2021 I have a G4x for the Mazda RX-7 running on a Series 6 FD3S. I'm having an issue with a fuel cut (sometime partial, sometimes a 100% cut) mysteriously kicking in during the warm up period. The issue seems to go away after the motor has been at operating temperature for a couple minutes. Notes: - happens at low RPM, well under 4000 RPM, so I don't think it's cold overrev protection - Happens at partial and very light throttle, cruising or very light acceleration - happens while still in vacuum, so it's not a boost cut - Lambda looks to be safe, so I don't think it's lean protection - lasts for 0.5" to 1.5" seconds - If I'm reading the logs correctly, I see 100% fuel cut and some ignition retard at 2:47.998ms section time, but NO ignition cut (which could be dangerous especially for a rotary, right?) - Up until that section time, everything looks conservative: TPS, RPM, AFR, Knock, MAP, IAT, Batt Voltage, etc. all look like they're well within limits. I've attached the current configuration and a datalog showing several instances of the fuel cut happening. If anyone has ideas or some insight, I'd appreciate it. Thank you. PC Datalog - 2021-02-3 12_24_08 pm.llgx 2021-02-03-v5.0.pclx Quote Link to comment Share on other sites More sharing options...
Iguanapeluda Posted February 7, 2021 Report Share Posted February 7, 2021 is It possible that you have a bad wastegate config ? yo have change from 0 to 100 of wastegate.... groovezog 1 Quote Link to comment Share on other sites More sharing options...
Adamw Posted February 7, 2021 Report Share Posted February 7, 2021 The limiter is due to the oil metering pump showing a fault condition, RPM is limited to 2000 when the oil pump is in fault. I'll have to check with engineering tomorrow what can trip that fault as it mostly appears to be working ok in your log. Im not sure if it is just because its not quite sitting on target or there is some other requirements. Quote Link to comment Share on other sites More sharing options...
groovezog Posted February 7, 2021 Author Report Share Posted February 7, 2021 1 hour ago, Adamw said: The limiter is due to the oil metering pump showing a fault condition, RPM is limited to 2000 when the oil pump is in fault. I'll have to check with engineering tomorrow what can trip that fault as it mostly appears to be working ok in your log. Im not sure if it is just because its not quite sitting on target or there is some other requirements. Hey, that's it. Thanks for always being so super helpful. Is there an easy way to turn off the limiter for this fault condition? Or change the limiter to also disable ignition as well as fuel? It just makes me very nervous of this happening while I'm in boost and under load. If fuel was cut without ignition, I'd blow my apex seals out for sure. I'm also premixing oil into the fuel, so although I'd like my Oil Metering Pump to continue working, it's not as critical for an intermittent fault. Thanks again. Quote Link to comment Share on other sites More sharing options...
Adamw Posted February 7, 2021 Report Share Posted February 7, 2021 Let me first find out what factors can trip the stepper limit. The fuel cut is not really an issue as if you were at high RPM/load it will be a total cut, there will be no combustion again until you are below 2000RPM. Quote Link to comment Share on other sites More sharing options...
Adamw Posted February 9, 2021 Report Share Posted February 9, 2021 @groovezog I will PM you a test firmware to try. Engineering believe they see an effect in the control behavior in your log that could cause a false fault trigger so have made some adjustments to some of the hard coded parameters in the steeper control function. Quote Link to comment Share on other sites More sharing options...
groovezog Posted February 9, 2021 Author Report Share Posted February 9, 2021 13 hours ago, Adamw said: @groovezog I will PM you a test firmware to try. Engineering believe they see an effect in the control behavior in your log that could cause a false fault trigger so have made some adjustments to some of the hard coded parameters in the steeper control function. Got it, thanks. I'll update the firmware and report back. Quote Link to comment Share on other sites More sharing options...
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