So I've scoured the threads to make sure I've captured all the forum advice first before posting my issue. I have a 2001 with about 50K miles.

At idle or slow speeds, my temperature shoots up to its limits 225 & 235but the fans kick in as they're supposed to and reduce the temperature but I hold my breath watching it vascillate in stop & go traffic. At cruise speeds, I am at a cool 190. So conventional wisdom says it is not an air flow issue.

I've been trouble shooting this problem for a while now.
Here's what I've done so far in no specific order:

• Checked both fans; they operate as designed
• No DIC codes, digital temperature agrees with analog
• Checked the radiator for debris
• No leaks seen on coolant lines or radiator + no loss of coolant over time
• Flushed the system twice now, the second time after I replaced the stock thermostat since it was a cheap part
• Checked to make sure the water pump hoses were hot

What is my next step? I suspect that it still might be a water pump but is there a good check for this? It doesn't look like a hard procedure to replace it.

Thanks folks

 

Well after re-reading your post, I would think that the temps might be a bit above normal, if I understand you correctly. But it would also depend on the ambient temps. (you don't list your location in your profile)

Are you saying that once the fans come on, the temp drops down?
Did you do a "power flush" or did you just drain the radiator?
A relevant anecdote:
When I first got my 2001 last August, it had some high temps, similar to what you described. I used the Prestone Flush n Fill kit that allows you to use a garden hose to flush the complete system, block and all, added a bottle of Water Wetter and a gallon of Dexron coolant, and topped off with tap water. I also replaced the thermostat with an auto parts store model. The car has been running significantly cooler since.

 

Normal behavior for a stock 01. Mine ran into the 230s idling in hot weather all the time (before mods).

Not sure what there is to troubleshoot? If you don't want it to get that hot, reprogram the fans, or install a more efficient radiator.

 

Normal behavior .....

Go stand a few feet in front of your car ..... notice a couple of things .....

* Unlike a "regular" car, the Corvette does not have a front "grille" for the radiator ..... The radiator draws air from under the nose, behind the airdam. If it is a hot day, in stop and go traffic, the air coming off the road surface can be over 100 degrees. If you have your A/C on the condenser gets the "fresh" air first, so it will heat the air further before it goes through the radiator.

* The engine is surrounded by body work ..... there is virtually no natural airflow through the engine compartment when the car is standing still. This means that hot air has no easy way out and simply stays in the engine compartment getting hotter and hotter.

If your Corvette isn't moving, a rising engine coolant temperature is absolutely normal. That's why the radiator has 2 fans to pull significant air through it when the coolant temperature rises above the programmed turn on point.

If you take your Corvette out on a day when the air temp is ... say .... 20 BELOW zero .... and park it with an idling engine .... I guarantee it will overheat if you disable the fans. It might take a little longer than if you did the same on a day where the air temp is 100 degrees .... but the design of the Corvette cooling system assumes that either the car is moving to get air flow, or it uses the fans to create air flow.

 

buy a real radiator and it will stay at 192-195 all day long no matter what the weather
the stock radiator is too small

 

i put in a dewit's rad...made some diff. but then i put in spal fans, and that made a big diff..fans reprog., and also changed out solid fog bezels to open ones,also a 180 stat...no more heat issues...good luck

 

And without fans you will still overheat if the car isn't moving. It'll just take a few moments longer .....

There are hundreds (thousands) of Corvettes driving around in places like Phoenix and Las Vegas in 100 plus degree weather with the stock radiator ... they have the A/C on and are running just fine.

I've run my car on the track at Willow Springs in 100 plus weather and had no problems. Now that was admittedly an HPDE ... if I had been racing I'd most likely upgrade to something like a DeWitt .... but for street driving the stock radiator is just fine.

 

When you checked the radiator fins for debris,did you remove the top cover over the condenser and radiator?

Removing this cover,which is located under the air bridge,will allow you to blow out the condenser fins from the inside. It's the best way to clear any accumulated sand and debris.

While you have the cover off,check to see if the foam rubber air seals are still in place on the condenser sides.Without these seals,some of the airflow could bypass the condenser and radiator.

 

Tell us where you live, that makes some difference. If you run too much under 200 you will loose some gas mileage and maybe have problems with emissions testing.

Have you cleaned the cooling fins? First blow out with compressed air, then with water. Since these things are bottom breathers they pick up a lot of dirt that will interfere with cooling. And ensure you have enough coolant.

If you are still paranoid, reprogramming the fans is all that I would recommend. No more than 10 to 15 degrees IMO. Unless you race, then its a different story.

Otherwise sounds like you have no issue at this time.

 

My 02 acted the same till I cleaned the crud from between the Rad and A/C condensor. I removed top cover then the whole fan assembly and washed all the debris out from back side and down between. Amazing the stuff that ran down the driveway.

Phil

 

I was in stop and go traffic the other day with the AC on in 111 degrees. Car never got over 207.....and I havent cleaned the radiator/condensor fins in over a year. :o

 

My 2000 actually behaves identically to this, exactly matches your temperature readings as well. I was worried about it as well to start with, then took a look at how the radiator is situated and where it is located. Can always change the thermostat, this is the solution I am choosing. There is also the fan remprogramming. God luck!!!

 

As I recall, the stock programming will not kick on the low speed fans until ~226 'F, and high speed fans at 235 I used to own a 2001 the same color
Where are you in CA? I have HPTuners with unlimited 01 license (among others ) and would reprogram your fans if you were nearby.


Stan

 

I was told this when i bought the car "take the top of the radiator apart and clean it every once in a while, these cars pick up a lot of crap" Well, when I put in the CAI, I had to take the top cover off of the radiator, and with the condensor and radiator sitting there, I proceeded to blow the two out with an airhose. He was right, I had so many leaves and debris in there. I hadn't had any cooling issues, but the fact is, these cars draw air from the road, and do pick up a lot of debris. My car sits right at 178 while driving around, but it will heat up to the 220 range in the middle of the day here in Tampa.

 

Thanks for all the feedback. I will have to absorb it all later on and make another post.

I live in San Jose, Ca area so temperature isn't a major factor overall. It just worries me that it jumps to the fan trigger temperatures in only a few minutes.

 

Spal makes a fans for our c5s that pull twice the cooling capacity than the stock ones ,someone else has mentioned the aftermarket fans,I know Ecs sells these Spal Fans For the C5 for 129.00 a fan, i would put the 2 spal fans in if your tight on money ,u May have to drill a hole or 2 in the old Shroud but it will get the job done & its cheaper than a new Dewitts Radiator ,also if u havent had the car tuned & are or wanting to add some mods to the car, u can have your tuner set the fans on @ 180 instead factory settings ,which i think is 220 any how good Luck with your problem ,its an easy fix

 

Unless you drive really short trips the thermostat won't do much. It may keep it cooler for a little while, but once it is fully open it can't do any more.

Unless you actually overheat, its not something that needs to be messed with for a street car. Clean the radiator and just drive your Vette and have fun. If you do actually overheat it is most likely that either you have something blocking the air flow or a leak that let the coolant get to low. Not that the system was engineered wrong. Even in Tucson!

IMO the only thing that could be done to a street car without compromising it too much is to have the fans come on 10 degrees earlier. That way it runs in the designed temp range.

If you track your Vette or have huge mods, then you will need additional cooling. But, I don't think thats the case here.

 

Noted, and you are right it is mostly a street car. I do plan to take it to some test and tunes now and again. At some point in the future I plan to mod it but the highest it will see this year is Vararam, gears and possible headers and x-pipe. Thanks for the advice!!!

 

When I did my cam I got so much sand/rocks/leaves/etc from between the radiator and condensor I still can not believe it. It only had 40K Seattle miles on it.

 

I had leaves/paper bag and animal fur.

I plan on a 180 T-stat and reprogram the fans.