Before anybody yells at me; yes I have read over all of the overheating issues on these forums. I have bled the lines, replaced the t stat, all three relays, and both temp sensors.

When I start it up when it's been sitting for several hours it turns over with ease and the timing seems to be running at it's best. Then after about a 15 minute drive under load the radiator cooling icon starts to shine. Temps on the analog gauge show from 185 to 210. Fans don't always turn on at this temp. If I turn the AC on they both kick on fine. Forcing them on seems to do no good for the actual engine temperature. This is evident because the timing seems to go a bit to ****, I hear engine knocks and when it heats up like this and I turn it off.... it doesn't turn over so well anymore. You know that really hot turn over sound that implies an engine under great stress. The water pump is supposed to be new. That was replaced with the engine rebuild under 5K miles ago.

When I first got the car before these summer months started it had enough power to make my wife hot as hell. Now only the car is hot as hell. Heats up, bogs down, impresses no one.

I don't have a scan tool yet as tunercat sent it to the wrong address and I am waiting on a solution to that. Once I get it I may possibly know more. For now I have to use the old manual methods. Any ideas what I can check, test or replace that I haven't replaced already?

Big Wil

 

Well, I may not have the answer to your problem but maybe just some more info to help troubleshoot. The stock fan temp is 226 deg for the first fan and 235 for the second so at 210 you wouldn't see the fan kick on. When did the problem start? Do you have a check engine light? (besides the coolant)

Brian

 

The "icon" on the dash is for low coolant. That's all it indicates and has nothing to do with indicating engine temps (unless the coolant is actually low). With all your research, I am surprised you did not run across threads about the low coolant sensor. It is a common problem child, indicating low coolant when it is not low.
http://shbox.com/1/4th_gen_tech2.html#low_coolant_lamp

Your engine temps don't seem to indicate any overheating. The timing issues could be from something else you have yet to discover. Maybe when you get to scanning it, you can see something more obvious. BTW, Tunercat is not a scanning program.

 

Yes I have read about the indicator for the low coolant being a bit buggy. I would write it off as a bad sensor except that it does correspond to the high temperature of something engine related.

If you started my car after 15 minutes of operation in this heat you would have the pleasure of hearing it's turn over and as several mechanics have told me, "Your engine is overheating". However, the brand new temp sensors still say it is below the standard operating temperatures. So although the gauges say one thing everyone's ear is telling them another.

Yet when you first start it for the day it fires off in an instant, no knocks, no timing fouling and doesn't have the low coolant indicator until it reaches temp.

Big Wil

PS. DataMaster Program is though isn't it. That's what they are sending me with the cables, etc.

 

As stated earlier it started when the summer days did about a month ago. It's to the point that I fear driving it in the heat. And no check engine light.

Big Wil

 

I also agree that it doesn't sound like it's really overheating. How can a mechanic 'hear' an engine overheat?

Having it scanned will likely result in code(s) that will point you in the right direction.

As for the low coolant light, if it's not working correctly, you might as well unplug it as I did. It is not connected to the computer, only the dash light (a working sensor is the best way to go of course).

 

mine is similar in the fact that once its hot, 210 or above, it also is slower on the startup. still starts, just sounds like it's struggling. heat stress on the starter maybe?

 

Ok, I replied at the same time as you, so nevermind about the SES light remark I made.

Part of your symptoms point towards a worn out battery. After having this Camaro for so long, I've realized the battery is in a location where it's subjected to alot of heat and not much air flow. I've replaced a few batteries after the heat has gotten to them (during the summer here in Florida). They started up the car fine, drove it down the road a couple miles, then it would barely turn the car over since the heat from the engine/nearby radiator warmed it up too much. Just an idea.

 

Ok then if it is ok that it sounds like I'm trying to start a 1942 humvee then maybe there isn't an issue in regards to coolant flow. My guess as heat expands and it's simply resistance on pistons and shafts. So I guess I should disconnect the coolant level indicator and start trying to find the cause of all that knocking and loss of power once it warms up to operating temperature. Or tell people to come race me in my driveway while it's cool.

Thanks for the assurances. I'll get to work on the next.....

Big Wil