check to see if your air dam is still on the car!!!!! mine was missing after a paint job and it was overheating like crazy! i took it to the stealership and they couldn't find out what was wrong.

this forum suggested checking the air dam for damage. turns out it was missing! I bought one, installed it and bam, no more overheating.

also, a few months back my coolant tank would spew out coolant but i wasn't getting the overheating light. It would spew out coolant like crazy and steam.

Once again the stealership had no F'ing clue!
Thanks to the forum once again, I found the problem!
My coolant tank cap was bad, and the tank had a hairline crack in it right where the small line is at the top.
I replaced the coolant tank and the cap and bam! once again, problem solved.

I also put in a new t-stat and flushed the coolant just in case.

Good luck with your ride man. Overheating issues suck and can cause alot of stress on you and the car.

 

Pellets ????? WTF ??????

That's BS .... I'd be very leary of a shop that tried to tell me I need "pellets" in the coolant.

The cooling system is pretty simple ... not much to go wrong .....

Water circulates through the engine by being "pushed" by the water pump. After it picks up heat it circulates to the radiator where it expels heat ... then back to the engine .....

The only "problems" that can occur are .....

Water not circulating properly ... bad thermostat or water pump. Since the thermostat is done, the water pump is a possibility. The pump is driven by the serpentine belt on the front of the engine. Do you hear any "unusual" noises coming from the front of the engine such as a squeal (belt slipping) or a rumbling sound (water pump bearing) ????

Not enough water/coolant .... unlikely since you said it was checked and OK at the oil change and the guys who replaced the thermostat should have filled it correctly. Check the cap on the coolant reservoir. It should be a pressure cap rated at 16 or 18 pounds. If the incorrect cap is on there (non-pressure) the coolant will boil at 212 degrees and the coolant's ability to pull heat from the engine drops to nothing once it boils .... I'd be suspicious that your cap is bad, and it's a cheap fix.

Air through the radiator .... since you say this is happening while you are driving this is somewhat less likely, however, it is easy to check. Once again check carefully under the nose of the car for a working air dam and no debris in the A/C condensor area. With the engine running and the coolant at at LEAST 185 degrees, turn on the A/C and see if the two fans behind the radiator start turning in LOW speed mode. If not, you have a fan problem.

Based on your description, I'd guess bad radiator cap or bad water pump, in that order.

Good luck,

 

Well, I guess it's too late. The problem as they said, was a clogged radiator in the middle tube/hose? I asked him to make sure that there was no debris in the fins to double check that and he said no, it was completely clean. They replaced the radiator (@ $350, cap, added new coolant, still had the pellets but the bill only said 7.99 and 2 1/2 hours labor. They took off the thermostat bill. Total was $680.

So, does this sound right? Should I have kept my old radiator?

 

Usually a blocked radiator exhibits two symptons, neither of which you mentioned in your previous posts ....

1) Over time, as the radiator becomes blocked, your "normal" operating temperature will start to rise. One day normal temperature will be 195 degrees ... a few weeks later it will be 200 ... and weeks later (as the blockage gets worse) it will be 210.

2) Once the blockage reaches a point that the radiator is no longer cooling effectively, the car will ALWAYS overheat. It won't let you drive one day with normal temperatures, and another day overheat.

My guess, and let me emphasize I am guessing, is that the radiator cap (actually the cap on the coolant reservoir) was not holding pressure correctly. As I said in a previous post, once the coolant temp gets to about 212 degrees with a bad cap, the engine temperature will rapidly rise from there, as boiling coolant does a VERY poor job of pulling heat from the engine. Because the coolant sensor is screwed into the metal of the head, it is showing you the temperature the metal in the engine is rising too at that point, as the coolant will stay at 212 (boiling) until it is all gone.

With modern additives such as Dexron, it is unusual to get a radiator blockage UNLESS the cooling system has been improperly maintained/serviced. Back in the 60's it was possible to get radiator blockages due to adding water that was high in mineral content, as it would tend to corrode the brass/copper used in radiators back then. With todays coolants and Aluminum radiators (and Aluminum engines) blockages are rare.

For the price they charged you you could have installed a DeWitts ( http://www.dewitts.com/ ) radiator that would have ensured that you NEVER have a cooling problem again.

Not trying to rain on your parade, but I'd think three times before I took the car back to that shop for any further service .... they screwed up the first time, and based on the bill for the second time, they aren't hurting for money .....

A GM radiator for a Corvette costs about $230.00 ( look it up on http://www.gmpartshouse.com ) so even the price they charged you is out of line (you said it was a $350.00 part) .... I'd stay away from that shop .....

You remind me of my g/f ... she took a car into a dealership a few years ago and they wanted something like $1,200.00 to fix the problem ... I talked to them on the phone and the price "magically" became $250.00 ......

When you have a problem post it here on the forum nd arm yourself with INFORMATION before letting a shop "decide" what is wrong with your car .... two places n America still are a real problem for the average consumer ... medicine and cars ... we just often don't know enough to question a diagnosis ....

 

Thanks for the tips everyone. I really wish I had the patience and time to read all your posts before making a decision. I know that dealership repair is always the last resort for me. That's why I had it taken to my friend's shop. Only thing is, he was on vacation until Tues. and wasn't answering my calls.

Black Z06, #2 you said that the car always overheats. Could it be possible that at first start, when the car is cold, it reads cold/normal until after driving for a while and creaping up to finally overheating?

What about having dual problems, like the blocked radiator along with the t-stat not opening? The consultant made it sound like it was both. No coolant flow to the radiator along with blockage. Also, I didn't quite understand what he was talking about when describing the middle tube being blocked. He said there was one in the middle and one on the lower section of the radiator.

If I remember correctly, when disputing the need to pay for the t-stat when that didn't fix the problem, he stated that the hose to the radiator was cold before the new stat while the others were hot, and after the new stat install, it was hot. So it was necessary regardless.

I still try to take a lot into consideration here if possible before taking on any kind of work on my car but, as I am not at the luxury of having another means of transportation, I had to make a quick resolution of the matter.

It would have saved me maybe a couple hundred if I had just waited one more day. In the end, the lesson I learned here is that there is lots of info here. I just have to be patient and smart about it.

 

IF the radiator hose was cold ( Are you sure this is a statement of fact ????) when the engine reached operating temperature (stock thermostat opens at about 190 degrees) then the diagnosis should be ....

1) thermostat .. except the stock thermostat is designed to fail OPEN ... so a bad thermostat would lead to unusually LOW temperatures and a "hot" radiator hose ....

2) Bad water pump ... it is not circulating the coolant ... "possible"

3) Blocked radiator ... or a blockage of some other part of the cooling system ..... (also possible)

Sounds to me like they are throwing parts at the problem ...... I can fix ANY overheating problem by replacing the radiator, hoses, thermostat, etc .....


BUT .... be aware that an overheating problem can also indicate issues such as a a bad head gasket ... which it doesn't sound like you have (problem is interrmmitent) .....

You need to take the car into someone you can REALLY trust .... a "friend" who is not available does not classify as fitting in this category.

The prices for parts you are quoting (if true) tell me they are taking advantage o0f you. You need to find a shop in your area that will take care of you .... service costs money ...... but be sure you are paying for the service .... not some guys throwing parts and labor (at your expense) to "fix" a real problem.

The fact they replaced the cap for the coolant leads me to believe the problem is solved, How you deal with how much you paid is up to you ..... but I think they took way more money than you should have paid ......

Steve

 

Sounds like they did to me too. I'm going to go check out the radiator and coolant cap to see if I can tell if they were replaced.

 

Is your car puking coolant out the reservoir cap when it overheats and leaking down the side? I had that problem on mine at all it needed was a new cap, (very common problem). Hoses where good, thermostat was ok, no air in system, water pump was good, no debris in radiator, fan coming on when it should, no leaks on anything else.

I had the GM dealership do a coolant flush and pressurize the system during this visit to replace the cap. Knock on wood - no problems last year at all.