[travislambert]

Originally Posted by Repman

Guys , I pick up my new ZL1 this friday , now I am questioning my decision to get a manual car instead of the auto. I am not a drag racer but will be taking it to the road course so dead stop launches are not what I will be doing with this car. Having said that is that the only time you experience the loss of power at drop clutch launches or is it pulling timing every time it senses some
wheelspin ? I would not be happy coming off a corner and having it cut power on me if the wheels spin a bit . Thanks for your input and sorry you are experiencing this issue.

Larry

It happens on take-off from a stop. It doesn't matter if you are driving easy from a stop light or trying to launch at the drag strip. The car appears to miscalculate the wheel slip and immediately pulls power. (I think it accomplishes this by closing the throttle blade...drive by wire)

I'll see if I can catch it on video the next time I drive the car. I have a drag strip video I can post up later that shows what it looks like from outside the car.

[Infern0]

I've only noticed it on my first forward motion after backing out of the garage (on cold start). ; but it's just about every single time. That first forward motion always feels like I am going to stall it no matter what, but sometimes I can hold the accelerator in the same position (just at the blip amount - less than 1/2 inch) throughout the bogging feeling, and I can immediately feel when the eLSD disengages and provides full output because my tires will give the tiniest spin and throw my head back like it just "caught" somehow.

[Repman]

Originally Posted by travislambert

It happens on take-off from a stop. It doesn't matter if you are driving easy from a stop light or trying to launch at the drag strip. The car appears to miscalculate the wheel slip and immediately pulls power. (I think it accomplishes this by closing the throttle blade...drive by wire)

I'll see if I can catch it on video the next time I drive the car. I have a drag strip video I can post up later that shows what it looks like from outside the car.

Thanks Travis, so if i am easing away from a light and stomp it in 1st gear at 5-10 mph it will shut down ? if that's the case there is definitely a programing issue or GM is trying to prevent warranty work from blown rear ends and half shafts.

[travislambert]

Originally Posted by Repman

Thanks Travis, so if i am easing away from a light and stomp it in 1st gear at 5-10 mph it will shut down ? if that's the case there is definitely a programing issue or GM is trying to prevent warranty work from blown rear ends and half shafts.

I notice the problem most as I am engaging the clutch on a slow takeoff. So at the point when it pulls power, the wheels are barely starting to move. Once the clutch is fully engaged, I haven't noticed this particular issue.

Originally Posted by Repman

if that's the case there is definitely a programing issue or GM is trying to prevent warranty work from blown rear ends and half shafts.

GM certainly has wheel hop protection and torque management to prevent warranty work, but this is different. The SS has wheel hop protection, torque management, etc. too, but I never noticed this issue with my '16 SS. The issue I am describing correlates very well with the erroneous wheel slip % calculation on the eLSD. The wheels won't be slipping at all, but the wheel slip % will suddenly spike and it immediately feels like you're no longer pressing the gas pedal. It is very difficult not to stall the car when this happens.

I speculate that this issue is the same as when the car falls on its face while slipping the clutch at the drag strip, but I don't know this for certain. Again, I'm aware of torque management pulling power, etc.. what I'm describing is similar but different.

[Repman]

Guys thanks for the info .

[travislambert]

Originally Posted by Repman

Guys thanks for the info .

No problem. Unless you're a hardcore dragstrip guy I wouldn't let this issue stop you from getting the car. The manual transmission makes the car a lot of fun. Hopefully GM will get this issue worked out one day and provide us all an update.

[Shorty45]

Just to echo what Travis said, I've only really dealt with this issue at a complete stop then start, usually at the drag strip. I found some info on the Corvette and Stingray forums. Here's one of the Corvette chassis engineers talking about what eLSD actually is. Fast fwd to 7:10
http://www.stingrayforums.com/forum/...ideo-more.html

[travislambert]

I sent a PM to the "Chevrolet Customer Svc" user on this forum to point them to this thread. Maybe we can get some traction from that angle.

[Repman]

Guys , thanks for all the input . I cant wait for my plane to land in Atlanta Friday so I can head home and pick up my new toy!

I'm new to this forum but I can see there is a lot of helpful , passionate car guys and gals here . I'm looking forward to my new car and being part of this community.

[Infern0]

Interestingly, I was watching it this am and was registering eLSD % while coasting down the road. Even with the clutch held in completely and rolling at 40MPH was fluctuating between 1-3%. As far as tire spin, in almost every gear actuation there was spin being registered, no matter how gentle. But with a spirited acceleration while already moving, kicking out the rear a little, didn't show anything. What's being done and what's being shown are different in some way.

[Can'tHave2MuchHP]

Wow this thread is very interesting. Keep us updated on this issue.

Is it possible that all you guys are seeing on the eLSD % screen is just Torque management in action?

[travislambert]

Originally Posted by Can'tHave2MuchHP

Wow this thread is very interesting. Keep us updated on this issue.

Is it possible that all you guys are seeing on the eLSD % screen is just Torque management in action?

I don't think so. In slow takeoffs with low RPMs <1500 and no wheels actually spinning, the wheel slip % will suddenly max out the display and power gets pulled. There would be no good reason to limit torque under those circumstances.

Under normal driving scenarios it's easy to see the wheel slip % calculation is not accurate. Normally it seems harmless, but sometimes I think it's so far off it causes the ECM to think it needs to pull power.

[LSmith353]

First, I should quantify my post here by saying I do not own a ZL1, nor have I driven one. But I read this section pretty much every day. The symptoms being described here seem similar to issues discussed in a previous thread about the rev limiter kicking in. http://www.camaro6.com/forums/showth...=493356&page=5 From what I can deduce from all of this, if your foot is even touching the clutch pedal in a ZL1, there is some form of logic at work to prevent damage to the drivetrain.

[Infern0]

Originally Posted by LSmith353

First, I should quantify my post here by saying I do not own a ZL1, nor have I driven one. But I read this section pretty much every day. The symptoms being described here seem similar to issues discussed in a previous thread about the rev limiter kicking in. http://www.camaro6.com/forums/showth...=493356&page=5 From what I can deduce from all of this, if your foot is even touching the clutch pedal in a ZL1, there is some form of logic at work to prevent damage to the drivetrain.

I didn't read through the whole thing again, but if I recall correctly that feature doesn't activate until 5000 rpm.