[StanZL1]

Need some help from the crowd.
Drives fine on street/highway.

Tracking at Mid-Ohio and the car is pulling power at it gets hot.
Full stock. 24k miles. About 2k miles of hard track use over past 2 years.
Minor note that race rims don't have tpms, never been an issue and set great lap times at other tracks in 2019 and 2020.

Shifts normally. Track Sport1 for the day since Mid-Ohio is a slick track and my 2nd time here.

Building power takes longer and longer in each successive straight.‘Sounds like’ timing retarding, but confirmed the blower coolant circuit is full (dealership specifically bled it before track) because I had that power pulling issue 3 months ago at Grattan Raceway. Slow power build to a point and then zero power as if no pedal control. Could possibly be more of the same, but now theres a different heat soak (?) symptom (rather than cutting all throttle response…)

Now it appears to hit a point in every long hard accel at wide open throttle around 5200rpm, the ECM takes over and begins oscillating the throttle… which sawtooths power even slower up to shift point. Friend got a logger and confirmed WOT pedal input, good fuel pressure, and the ECU is taking over controlling the car (some protective loop). Haven’t figured out yet “what” sensor or condition is causing the ECU to cut & give throttle over and over (every straight) until it cools down (in the brake zone & corner esses) and returns to driving like normal.

Drives on pits/street/highway just fine when cool.
Zero codes stored.

Dealership visit tomorrow.

[EDFHOBBIES]

was told by a friend timing is pulled when IAT3 or MAT in HP reads 150 degrees.

[Camaro1973]

Originally Posted by StanZL1

Need some help from the crowd.
Drives fine on street/highway.

Tracking at Mid-Ohio and the car is pulling power at it gets hot.
Full stock. 24k miles. About 2k miles of hard track use over past 2 years.
Minor note that race rims don't have tpms, never been an issue and set great lap times at other tracks in 2019 and 2020.

Shifts normally. Track Sport1 for the day since Mid-Ohio is a slick track and my 2nd time here.

Building power takes longer and longer in each successive straight.‘Sounds like’ timing retarding, but confirmed the blower coolant circuit is full (dealership specifically bled it before track) because I had that power pulling issue 3 months ago at Grattan Raceway. Slow power build to a point and then zero power as if no pedal control. Could possibly be more of the same, but now theres a different heat soak (?) symptom (rather than cutting all throttle response…)

Now it appears to hit a point in every long hard accel at wide open throttle around 5200rpm, the ECM takes over and begins oscillating the throttle… which sawtooths power even slower up to shift point. Friend got a logger and confirmed WOT pedal input, good fuel pressure, and the ECU is taking over controlling the car (some protective loop). Haven’t figured out yet “what” sensor or condition is causing the ECU to cut & give throttle over and over (every straight) until it cools down (in the brake zone & corner esses) and returns to driving like normal.

Drives on pits/street/highway just fine when cool.
Zero codes stored.

Dealership visit tomorrow.

Best to log it and see for yourself. But. on a stock tune at 56C/132F timing can start to be pulled for high air temps and at 194F ECT table can start pulling timing as well. Only way to check is to have a gauge or log it.

[StanZL1]

Much appreciate the feedback. I understand that retarding timing will drop power. Unclear how how that leads to the ECM to disregard pedal position, closing the throttle momentarily, then back to pedal input, repeat 2-3 times a second. I will share with the dealership, but unclear what part(s) to replace. Bad sensors? Bad blower? Bad blower cooling circuit or pump?

We did check and see temp drop across the s/c heat exchanger.

[Camaro1973]

Originally Posted by StanZL1

Much appreciate the feedback. I understand that retarding timing will drop power. Unclear how how that leads to the ECM to disregard pedal position, closing the throttle momentarily, then back to pedal input, repeat 2-3 times a second. I will share with the dealership, but unclear what part(s) to replace. Bad sensors? Bad blower? Bad blower cooling circuit or pump?

We did check and see temp drop across the s/c heat exchanger.

Could be so many things. A shop will most likely log what the car is doing exactly at the time it happens. Much easier to troubleshoot when you have data.

[Stephen12ZL1]

if the ECM retards due to a high MAT or other parameter, it will seem like the car will restrict RPM like a throttle closure. I have witnessed this in a 2018 ZL1...a close friend's car. He had air in his supercharger circuit and this caused an abrupt loss of power. You need to check data and double check the supercharger circuit. Get a reservoir and you won't have this problem anymore.

[StanZL1]

Dealership still thinks air is in the S/C cooling circuit; won't bleed without the J-Tool that no dealership in SE Michigan appears to have. Currently calling around shops in the area to confirm that.

So I may have to do this the manual route anyways: include the car, build a funnel, press in the valve with a pole... etc. Take a few hours to get all the bubbles out.

** Anyone know the pinout to jumper power to the S/C fan? ***

Thought I saw a decently priced kit somewhere... any hyperlinks are much appreciated!

[Evansa22]

Somewhere i read the bleed/fill port is a potential failure point, possibly slowly letting air in after they purge it. Jannetty now sells the appropriate tool for bleeding/filling the Intercooler circuit. There are also cheaper plastic adapters for filling it, I bought one and they work well

[Gunkk]

Originally Posted by Evansa22

Somewhere i read the bleed/fill port is a potential failure point, possibly slowly letting air in after they purge it. Jannetty now sells the appropriate tool for bleeding/filling the Intercooler circuit. There are also cheaper plastic adapters for filling it, I bought one and they work well

I have one of those $15 plastic adapters. Forgot where I bought it but there's a link somewhere in the bowels of these forums.

Also, here's a $75 surge tank you can add to your SC loop, probably the best option if you are tracking frequently (since you can see it and fill easily at the track if needed):
https://www.good-win-racing.com/Mazd...ml?id=U3Y75wqS
and a handy how-to install thread:
https://www.camaro6.com/forums/showt...4#post10657804

[HDRDTD]

Originally Posted by StanZL1

Dealership still thinks air is in the S/C cooling circuit; won't bleed without the J-Tool that no dealership in SE Michigan appears to have. Currently calling around shops in the area to confirm that.

So I may have to do this the manual route anyways: include the car, build a funnel, press in the valve with a pole... etc. Take a few hours to get all the bubbles out.

** Anyone know the pinout to jumper power to the S/C fan? ***

Thought I saw a decently priced kit somewhere... any hyperlinks are much appreciated!

Here's the one i bought. Couldn't be easier to use, no tools required.
https://jannettyracing.com/products/...cadillac-cts-v


No need for the J-tool. Just hook it up, fill it with 50/50 Dexcool, and run the engine for a bit. You can watch the level in the bottle while running and coolant is flowing. Any trapped air will result in bubbles in the bottle.
Once the air bubbles are gone, you can still see the fluid in the bottle stir just a bit with the fluid flow.

Yes it's pretty much just a factory cap that's been drilled to attach the bottle to, and the bottle provided is just a soda bottle with the bottom cut off, but it works just fine.

I used it on my 2013 ZL1 that had a few track days on it in the last 9 years but nothing extensive, and yes a few small bubbles came out, probably used maybe an ounce or two of new Dexcool.

[willzilla]

Originally Posted by StanZL1

Dealership still thinks air is in the S/C cooling circuit; won't bleed without the J-Tool that no dealership in SE Michigan appears to have. Currently calling around shops in the area to confirm that.

So I may have to do this the manual route anyways: include the car, build a funnel, press in the valve with a pole... etc. Take a few hours to get all the bubbles out.

** Anyone know the pinout to jumper power to the S/C fan? ***

Thought I saw a decently priced kit somewhere... any hyperlinks are much appreciated!

Could pick up one of these.. https://lsa-conversion-store.myshopi...sivoir-upgrade

Has a built in air bleeder thingie.

[Joshinator99]

OP: didn’t see in your post what you’re running for fuel?

[gtfoxy]

Originally Posted by StanZL1

Dealership still thinks air is in the S/C cooling circuit; won't bleed without the J-Tool that no dealership in SE Michigan appears to have. Currently calling around shops in the area to confirm that.

So I may have to do this the manual route anyways: include the car, build a funnel, press in the valve with a pole... etc. Take a few hours to get all the bubbles out.

** Anyone know the pinout to jumper power to the S/C fan? ***

Thought I saw a decently priced kit somewhere... any hyperlinks are much appreciated!

Give this a try.

https://www.coolerbleeder.com/the-cooler-bleeder

Picking one up soon myself.

[StanZL1]

Much appreciate all the replies.
Running 93 Octane.
No codes in the computer.
Dealership swears he put 6oz more in it when it was bled in June with the J-tool.

Also looking and the CoolerBleeder Kit.
Watches some youtubes of filling with a 2-litre bottle.

Sounds exactly like this... and I think I need to get the LSA Cov kit.
https://www.camaro6.com/forums/showt...4#post10657804

Thanks all!