okay so heres the story. A family member of mine was driving my Z06 back from a Car show, while i was ahead of them in my GTO. It was raining and the Z06 Hydroplanned off the road into a ditch and hit a Chain link fence.

Long story short I drive the car out of the ditch and start taking it the 1.5 miles to the garage. (accident Happened about a mile and a half from HOME of Course) at about 4 blocks from the house the message center starts flashing Check Gauges. I look and the Coolant Temp is at 260 degrees!!! so i rush to get it into the drive make the final turn and the message center displays reduce power. Then the car shuts off. So i let it sit awhile. Start the Car back up and it runs fine pull the car in the garage and evaluate the Body damage. I notice that the radiator is bent and broken along with both rockers broken and the passenger fender destroyed.

The car is almost done now from a Rod and Custom shop. all they have done is the body work. So what i am worried about is how bad could the motor be damaged???

Before the radiator was replaced and the body work started i had to load the car on our car trailer. Before i did so i filled the radiator Full with water and left the garden hose run slightly with the cap off. I started the car and let it warm up to about 190 coolant and 110 oil. with the cap still off i reved the motor up to about 6800rpm a couple times and using my scan guage incountered no Misfires, DTC codes, or Knock Retard. So i shut the hose off put the cap on and drove the car onto the trailer. Reved it a couple more times (coolant temp at about 210 and 120 on oil temp, and no DTCs, Misfires, or Knock Retard. also no spikes in Temperature the car was probly running 15 mins total. 5 of which were after i removed the garden hose and put the cap back on the tank.

does anyone think something could be wrong with the motor or am i just worrying to much?????

FWIW its a Forged 347ci LS6 - diamond pistons, Probe LW rods, ported LS6 heads, Total Seal Rings, Clevite H series mains, etc.

 

No real way to tell until you can actually drive the car, but I think you will be ok,these motors are plenty strong and you didnt drive it very far.

 

are GM MLS headgaskets known for taking decent abuse??
Thats what type of headgaskets are on it now.

 

I had mine do the same thing just a couple weeks ago. Most likely, your are fine. (you can breath now) I threw my belt, and had the same situation with temp, and mine is completly ok. No probs at all.

But, just keep an eye on it when you get it back together. Just in case the thermostat stuck or something...

 

LOL on the Breathing comment!!!!

Ive barely got a full nights sleep since this accident has happened 3 weeks ago with all the ifs and buts going through my head. And to top it all of the biggest car show in nebraska (at my home town) is this weekend and theyre saying the Z06 will be done by friday afternoon!!!!!!!!! So this motor thing has been driving me up the wall.

FWIW I dont think i will ever buy another sports car after ived owned a Vette!!!! i like my GTO but the Z06 FTW!!!!!!!

 

so does anyone think that i couldve warped the heads or pushed out a head gasket????

Or am i worrying entirely too much?

 

If I read your description correctly the radiator was damaged but its now all fixed?

The engine has an automatic function to try to keep temperatures down. Here's the description from the manual:

The powertrain control module (PCM) uses the engine coolant temperature (ECT) sensor to monitor the engine for an over temperature condition. This condition occurs when the coolant temperature is above 131°C (268°F). When an over temperature condition is present, DTC P1258 will set. The PCM will disable two groups of four cylinders by turning OFF the fuel injectors. By switching between the two groups of cylinders, the PCM is able to reduce the temperature of the coolant.

Mind you it suggests that you should have seen a P1258 on the DIC if the auto protect cut in. It doesn't mention going into "limp Home Mode" in the book but that seems logical if the PCM goes for a partial shut down.

If you didn't drive too far with really high temps I'd say you'd be OK but I guess you'll know quite quickly once you drive the car again. The LS6 is a robust engine so hopefully all's well.

 

my message center Displayed the Reduce Power Message. about a block before i pulled the car into the drive. then as soon as i pulled in it shut the car off.

As for knowing when i drive the car what should i look for???

As ive said in the first post the very next day i filled the broken radiator and let the car warm up to to around 190 coolant temp reved it up a few times. Then check for DTC's. After i didnt find any i drove the car about 4 blocks to where the car trailer was located. Then pulled the car onto the trailer (with water running out from the Radiator of course) It showed my temp at 220. I reved it a couple more times and no DTC's. so then i shut the car down and hauled it to the Body shop. would this test been enough to know if something was wrong??