Z28 temp gauge gone mad after trackday - Camaro5 Chevy Camaro Forum / Camaro ZL1, SS and V6 Forums

docwra · 11-14-2022, 05:41 AM

Hi guys
I'm on a Zandvoort trackday at the moment in my z28, car has been great all morning but just got back in it to go for lunch after letting it cool down for 20 mins and the temp guage has gone straight into the red after 2 minutes of normal driving.
Radiator is cool, pipes going to it are warm but not massively hot and everything else is as normal.

My best guess is the temp sensor but could waterpump have failed? Any other ideas? I've got a couple of hours to drive home, is it worth risking it?

Should also add that it got a bit unhappy after a top speed run yesterday throwing intermittent engine light but has been absolutely fine today until now.

Thanks in advance etc, why does this have to happen in a foreign country though? 🙄

FASTFATBOY · 11-14-2022, 06:20 AM

Check coolant level

ariZona28 · 11-14-2022, 10:06 AM

It's possible the wire for the coolant sensor is grounding out or the sensor is bad. What was the reading on the DIC? What was the oil temp? Any codes from the CEL the day before? If the water pump failed you'd know it as the coolant would have quickly boiled over. If I recall correctly your car is a highly modified track car. You may want to consider getting a good trailer and truck with a few support tools and parts and also have a knowledgeable friend with you during track events.

docwra · 11-14-2022, 10:24 AM

Looks like it was airlocked, let it cool down and ran it up to temp with the rad cap and expansion tank off and it was fine ..... until I started to go home, then it did it again

My guess is the rad cap isn't up to heavy track use, must be getting air in from somewhere ��

docwra · 11-15-2022, 03:47 AM

Quote:

Originally Posted by ariZona28

You may want to consider getting a good trailer and truck with a few support tools and parts and also have a knowledgeable friend with you during track events.

We dont see a lot of LS7s in our part of the word so I thought Id ask the knowledgeable people here in case there was a known issue.
Thanks for the advice but I was with plenty of friends and a couple of race teams, Ive only been doing trackdays for 25 years - this particular trip included Spa, Nurburgring and Zandvoort.

And FWIW if youre going to trailer the car whats the point in keeping it street legal, you might as well take a racecar on slicks, no?

Z/28Dan · 11-15-2022, 05:48 AM

Quote:

Originally Posted by docwra

We dont see a lot of LS7s in our part of the word so I thought Id ask the knowledgeable people here in case there was a known issue.
Thanks for the advice but I was with plenty of friends and a couple of race teams, Ive only been doing trackdays for 25 years - this particular trip included Spa, Nurburgring and Zandvoort.

And FWIW if youre going to trailer the car whats the point in keeping it street legal, you might as well take a racecar on slicks, no?

Is your thermostat stuck? That is easy to replace if you can find one in the UK.

docwra · 03-12-2024, 09:17 AM

Probably time for an update ...... strap in, its been an exciting ride.

Got the car back home after the trackdays put it onto an OBD and saw various codes related to breathing and the evap system.
Went through all of the pipes/hoses and found that one was pretty severely kinked, straightened it out and all seemed to be well again. Took it out a couple of times and then put it away for winter.

I didnt drive the car again for a few months, but within 20 minutes it overheated to the point of blowing its head gasket.
I sent it to the best LS guy in the UK https://dynotorque.co.uk/ and although he was puzzled that the HG had gone - in his words "LS7's dont do head gaskets" - he found it had breached, he also found a piston had cracked.

He also discovered one of the aftermarket sports cats had detached itself and was partially blocking the exhaust, quite likely what caused the problem as it broke while I was doing around 170mph on a German Autobahn.
All fixed, no worries, I still remember him saying "you were lucky it didnt crack the block" when I collected it
Drove it carefully for a week and then let loose ....... and it overheated again.
Back on the recovery truck, back up to Birmingham and you guessed it, the block was cracked.

Fast forward 3 months, add another head gasket, another set of bearings, a replaced cylinder liner, a much lighter wallet and about a week more of sub 4K running in to go and my main takeaway is:

If youve got aftermarket cats fitted keep an eye on them.

The guys that did the machining was also 100% that the existing liners were not standard, anyone heard of this before?

aris · 03-12-2024, 11:59 AM

I also blew up some aftermarket cats after a few track events!

I was lucky to discover it before anything serious could happen, but both mufflers were completely clogged with cat material.

docwra · 03-12-2024, 12:24 PM

Mine was literally wedged up against the lambada sensor otherwise it would have fallen out (probably better TBH):

Bonus pic of cracked piston too:

NoDakZ/28 · 03-12-2024, 01:12 PM

Quote:

Originally Posted by aris

I also blew up some aftermarket cats after a few track events!

I was lucky to discover it before anything serious could happen, but both mufflers were completely clogged with cat material.

Quote:

Originally Posted by docwra

Mine was literally wedged up against the lambada sensor otherwise it would have fallen out (probably better TBH):

Care to let us know the brand? For what high flow cats cost these days thats unacceptable.

aris · 03-12-2024, 01:34 PM

Quote:

Originally Posted by NoDakZ/28

Care to let us know the brand? For what high flow cats cost these days thats unacceptable.

Mine came with my ARH long tubes. But I actually don't think it's uncommon for cats to get blown out after heavy track use. I'm not sure they are intended to run at high temps for prolonged periods.

I decided to hollow them out and run catless rather than trying another set of cats.

NoDakZ/28 · 03-12-2024, 01:51 PM

Quote:

Originally Posted by aris

Mine came with my ARH long tubes. But I actually don't think it's uncommon for cats to get blown out after heavy track use. I'm not sure they are intended to run at high temps for prolonged periods.

I decided to hollow them out and run catless rather than trying another set of cats.

I was afraid you'd say ARH ha, I just purchased their short system. Although we don't do much track day events I do autox and the occasional trip to Mexico. Thanks for the info!

docwra · 03-13-2024, 02:35 AM

Quote:

Originally Posted by NoDakZ/28

Care to let us know the brand? For what high flow cats cost these days thats unacceptable.

I dont know the brand, they were part of the Redline phase 3 package: https://www.redline-motorsports.net/...maro-packages/

Quote:

Originally Posted by aris

But I actually don't think it's uncommon for cats to get blown out after heavy track use. I'm not sure they are intended to run at high temps for prolonged periods.

Yeah, from speaking to people more knowledgeable than me it seems this is the case, if youre on track and cats arent OE youre better off without them.
My concern is that its going to be louder, it was close to noise limits here already, I guess theres only one way to find out ........

highrevving · 03-13-2024, 10:46 AM

Quote:

Originally Posted by NoDakZ/28

I was afraid you'd say ARH ha, I just purchased their short system. Although we don't do much track day events I do autox and the occasional trip to Mexico. Thanks for the info!

Wait a minute....trip to Mexico?

11-14-2022, 05:41 AM	#1
docwra Drives: 2015 Z28 Join Date: Feb 2022 Location: Cambridge UK Posts: 129	Z28 temp gauge gone mad after trackday Hi guys I'm on a Zandvoort trackday at the moment in my z28, car has been great all morning but just got back in it to go for lunch after letting it cool down for 20 mins and the temp guage has gone straight into the red after 2 minutes of normal driving. Radiator is cool, pipes going to it are warm but not massively hot and everything else is as normal. My best guess is the temp sensor but could waterpump have failed? Any other ideas? I've got a couple of hours to drive home, is it worth risking it? Should also add that it got a bit unhappy after a top speed run yesterday throwing intermittent engine light but has been absolutely fine today until now. Thanks in advance etc, why does this have to happen in a foreign country though? 🙄

11-14-2022, 06:20 AM	#2
FASTFATBOY Drives: 2013 ZL1 Join Date: Nov 2018 Location: Mobile Al Posts: 302	Check coolant level __________________ 2013 ZL1 M6, 2.4 pulley and a few bolt ons. 590 wheel and 11.70@122 on a hard tire.

11-14-2022, 10:06 AM	#3
ariZona28 Give speed a chance Drives: 2015 Camaro 2LS, 2015 Camaro Z/28 Join Date: Nov 2019 Location: Mesa, Az Posts: 2,233	It's possible the wire for the coolant sensor is grounding out or the sensor is bad. What was the reading on the DIC? What was the oil temp? Any codes from the CEL the day before? If the water pump failed you'd know it as the coolant would have quickly boiled over. If I recall correctly your car is a highly modified track car. You may want to consider getting a good trailer and truck with a few support tools and parts and also have a knowledgeable friend with you during track events. __________________ 2LS: a TREMENDOUS machine. Z/28: it's a BIT MORE POWERFUL, of course.

11-14-2022, 10:24 AM	#4
docwra Drives: 2015 Z28 Join Date: Feb 2022 Location: Cambridge UK Posts: 129	Looks like it was airlocked, let it cool down and ran it up to temp with the rad cap and expansion tank off and it was fine ..... until I started to go home, then it did it again My guess is the rad cap isn't up to heavy track use, must be getting air in from somewhere ��

03-12-2024, 09:17 AM	#7
docwra Drives: 2015 Z28 Join Date: Feb 2022 Location: Cambridge UK Posts: 129	Probably time for an update ...... strap in, its been an exciting ride. Got the car back home after the trackdays put it onto an OBD and saw various codes related to breathing and the evap system. Went through all of the pipes/hoses and found that one was pretty severely kinked, straightened it out and all seemed to be well again. Took it out a couple of times and then put it away for winter. I didnt drive the car again for a few months, but within 20 minutes it overheated to the point of blowing its head gasket. I sent it to the best LS guy in the UK https://dynotorque.co.uk/ and although he was puzzled that the HG had gone - in his words "LS7's dont do head gaskets" - he found it had breached, he also found a piston had cracked. He also discovered one of the aftermarket sports cats had detached itself and was partially blocking the exhaust, quite likely what caused the problem as it broke while I was doing around 170mph on a German Autobahn. All fixed, no worries, I still remember him saying "you were lucky it didnt crack the block" when I collected it Drove it carefully for a week and then let loose ....... and it overheated again. Back on the recovery truck, back up to Birmingham and you guessed it, the block was cracked. Fast forward 3 months, add another head gasket, another set of bearings, a replaced cylinder liner, a much lighter wallet and about a week more of sub 4K running in to go and my main takeaway is: If youve got aftermarket cats fitted keep an eye on them. The guys that did the machining was also 100% that the existing liners were not standard, anyone heard of this before?

03-12-2024, 11:59 AM	#8
aris Drives: Z/28 Join Date: Jan 2015 Location: Bay Area Posts: 276	I also blew up some aftermarket cats after a few track events! I was lucky to discover it before anything serious could happen, but both mufflers were completely clogged with cat material.

03-12-2024, 12:24 PM	#9
docwra Drives: 2015 Z28 Join Date: Feb 2022 Location: Cambridge UK Posts: 129	Mine was literally wedged up against the lambada sensor otherwise it would have fallen out (probably better TBH): Bonus pic of cracked piston too: