Hi,
2016 Camaro V6 3.6L LGX w/manual M6 transmission, E82 ECU, car is all stock right now. I've been trying to use HPT to resolve an old problem I've had since the car was new.
Basically as I'm releasing the clutch, the RPMs seem to shoot up and down once or twice until the clutch is mostly released, and then things settle down and it drives normally.
The effect is that when doing a moderate, normal takeoff from a start, or shifting 1st->2nd, the car lags or bucks and won't engage the clutch smoothly because the RPMs are oscillating up and down while I'm releasing the clutch pedal.
I've read dozens of forum posts about issues that sound similar to this. I've already tried adjusting or disabling the following settings, which didn't help:
- Idle -> "Launch assist"
- M6 spark smoothing
- Fuel -> Cutoff settings like CFCO, Manual Gear Type, Use Predicted Torque, Switchover Delay, NLS, Commanded Torque limits
It feels like one or two things is going on:
- When I get the clutch pedal released maybe 30%, some kind of 'launch helper' algorithm kicks in and increases the engine demand; then, as I let out the clutch pedal past maybe 70-80%, the extra engine demand goes away and the throttle pedal responds normally again.
- And/or, when the extra engine demand kicks in, it hits some kind of limiter and the ECU cuts spark and throttle temporarily until the RPMs reduce, then the throttle and spark go back up again.
Here are some of the many threads I've already been through, but the solutions given didn't seem to help in my case:
https://forum.hptuners.com/showthrea...ts-6spd/page2&
https://forum.hptuners.com/showthrea...t-issues/page2
https://forum.hptuners.com/showthrea...-Launch/page2&
The attached log shows a demonstration -- look near the end starting at 16:02:48, where I go through 6-7 cycles of this. I'm doing a gentle takeoff from a stop, and you can see the Absolute Load shoot up way past 100%, then it cuts timing and throttle even though I'm holding the throttle pedal steady the whole time.
What I'm looking for:
- Is there a table where I can shut off the extra 'throttle assist' or whatever, that kicks in when I'm releasing the clutch? I've driven a stick all my life and don't need or want any extra 'help' from the ECU!
- Are there any other tables that could be added to HPT for this ECU, that would let me fix this?
- Can the ECU OS be upgraded or fixed not to do this 'assist'?
I know this is not a common ECU or engine platform, but if someone can help me fix this it would make a huge difference in drivability on this car and for anyone else suffering with this problem.
Attached is my stock tune, current tune and log file. Let me know if I can provide any other logs or info.
Thanks!!
-Paul
Log from current tune: scan1_09102023.hpl
Layout for the log: scan1.Layout.xml
Stock tune: stock_06092022.hpt
Current tune: read_09102023.hpt