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Thread: I SMOKED a Focus ST in my cruze... But after car fully warm, only 50% throttle??

  1. #1
    Tuner
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    Thumbs up I SMOKED a Focus ST in my cruze... But after car fully warm, only 50% throttle??

    I cannot figure this out for the life of me. So, I have had an issue where when I have been datalogging (running speed density, open-loop) where after a bit of driving, my wideband reads full lean, and I am limited to like 10psi when I usually sit at 22-24.

    Now, this morning on the way tot he gas station shortly after starting the car (car at like, half of operating temp, unfortunately no log, but I need to check my android head unit. I thknk obdlink may have caught the log), I pulled up to a stop light with some car (it was dark), I give it some gas in 1st, this cat wants to go, and I give him the F***IN BUSINESS! When I slowed down, after gapping him by 2 car-lengths, I see it's a boosted focus... That was f***in sweeeeeet. I was so pumped. I put in gas, chilled for a minute, care was running just like it was, and about a mile down the road, I had a massive loss of power. I pulled over, checked my log, nothing stood out. Started, drove, hella fast, then about a 1/2 mile in... lack of power again.

    My car/engine is fine. Little-to-no knock. (we are talking decimal points.). It has to be some sort of limp mode triggered by temp (maybe cat temp?). I have no frikkin clue. Happydance immediately followed by WTF. lol.

    What temp-based tables should I be checking to remedy this. I tested a few times on the way to work, and if I pull over, kill the car, and just wait a few, wideband reads perfectly, car is fast, shortly after, car is slow and wideband reads full lean. My knee-jerk thought is something related to temperature. Please give me a hand; I see that dude around all of the time and I want to dust him again. lol

    Here is a snapshot of my channels and their data at full throttle when it's slow. Does anything stick out to you guys? My vve is dialed in VERY, VERY well. I spend the last two months doing it at least twice per day. All my stuff was well within tolerance when I dusted that dude (I have gauges and pay attntion, I was getting what I commanded, kpa where I set it, etc. ).

    Again, this is when I am being limited (the channel listing/values below.). As you can see, My foot is to the floor, desired agrees (mostly) with delivered accelerator position, but ignores my ACTUAL throttle position, but only after driving it a bit. I am almost certain it's something related to temp, but I have no clue what.

    Name Value
    Control Module Voltage 14.80 V
    Engine RPM (SAE) 4,941 rpm
    Vehicle Speed (SAE) 65 mph
    Throttle Desired Position 50.1 %
    Accelerator Pedal Position 99.6 %
    Throttle Position 49.8 %
    Mass Airflow Sensor State MAF Failed

    Engine Coolant Temp 185 ?F
    Manifold Air Temp 56 ?F
    Ambient Air Temp 32 ?F
    Intake Air Temp (SAE) 54 ?F
    Injector Tip Temp 87 ?F
    Intake Valve Temp 429 ?F

    Barometric Pressure Sensor 3,941.2 mV
    Manifold Absolute Pressure - Hi-Res 18.9 psi
    Barometric Pressure 14.7 psi
    Manifold Absolute Pressure Sensor 2,254.9 mV
    Desired Boost 187 kPa
    Turbo Bypass DC 0.0 %
    Cylinder Airmass 0.48 g
    Volumetric Efficiency Airflow 0.0789 kg/s

    Power Enrichment On
    AEM - EQ Ratio 1.120 λ
    Equivalence Ratio Commanded (SAE) 0.800 λ
    AEM - AFR 1.120
    Air-Fuel Ratio Commanded 11.30
    O2 Voltage B1S1 0.877 V
    O2 Voltage B1S2 0.946 V
    Short Term Fuel Trim Bank 1 (SAE) 0.0 %

    Timing Advance (SAE) 18.0 ?
    Base Advance 14.5 ?
    Coolant Advance 0.0 ?
    PE/COT Advance 0.5 ?
    Torque Mgt Advance 0.0 ?

    Piston Slap Retard 0.0 ?
    Knock Retard 0.0 ?
    Burst Knock Retard 0.0 ?
    Knock Retard Cyl 1 0.0 ?
    Knock Retard Cyl 2 0.0 ?
    Knock Retard Cyl 3 0.0 ?
    Knock Retard Cyl 4 0.0 ?
    Total Knock Retard 0.0 ?

    Instantaneous Fuel Flow Estimate 7.0 g/s
    Fuel Pressure Requested 58 psi
    Fuel Pressure Estimated 59 psi
    Fuel Pump Commanded DC 60.4 %
    Fuel Pressure Sensor 2.80 V
    Desired Fuel Pressure 58 psi

    Injector Flow Rate 33.37 lb/h
    Injector Pulse Width Avg. Bank 1 10.1 ms
    Fuel Pressure (SAE) 58.7 psi
    Advance Fuel Flow Estimate 6.7 g/s

    Predicted Axle Torque Source Driver
    Predicted Engine Torque Cmd 372 lb?ft
    Immediate Engine Torque Cmd 106 lb?ft
    Driver Pedal Axle Torque Req 2,361 lb?ft
    Driver Final Axle Torque Req 2,035 lb?ft
    Predicted Axle Torque Cmd 2,035 lb?ft
    Predicted Engine Torque Source Axle
    Delivered Engine Torque 109 lb?ft
    Engine Torque 109 lb?ft
    Peak Engine Torque 295 lb?ft
    Immediate Engine Torque Source None

    Intake Cam Des Angle 18.4 ?
    Intake Cam Angle 18.6 ?
    Intake Cam Error 0.0 ?
    Exhaust Cam Des Angle 18.6 ?
    Exhaust Cam Angle 18.8 ?
    Exhaust Cam Error 0.2 ?
    Misfire Current Cylinder #1 0
    Misfire Current Cylinder #2 0
    Misfire Current Cylinder #3 0
    Misfire Current Cylinder #4 0
    Total Misfires 0


    Your time is much appreciated. Thank you.

  2. #2
    Advanced Tuner ZeroBoostBuick's Avatar
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    Most of the time when a car goes into a limp mode, it gets OBD codes which can be helpful to narrow down the issue.

    I had limp mode happen only 2 times on 2 different cars and both times it was Transmission related.

  3. #3
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    It didn't. I figured it out. It only did it when I updated to the new editor beta version. Flashing the same tune back using the stable version fixed it right up and it did it without an obd code. That was what lead me to try that.

  4. #4
    Advanced Tuner ZeroBoostBuick's Avatar
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    OK thanks for the update.

    I had weird hick up happen years ago. Under full throttle a couple seconds into the pull the AFRC went back to 14.7 !!!. Good thing that motor was great at keeping KR at bay and nothing happened. Didn't even get a blip of KR. But as soon as it flipped the AFRC to 14.7, I could hear the engine sound different and lifted the throttle instantly.

    I re-flashed the car right away and never happened again.