[Scarletredline2008]

We have a 2008 Sky bought original with 53K miles. In 2010, we parked the Sky in my work underground garage and leased a car as we didn't want to put many miles on the Sky as it's my wife's car and she and I want to keep it forever (or close!). Well, I covered it and every two to three months, I uncovered it and drove it 15/20 miles or so to exercise it. After three years of this, one hot summer day with the a/c on, the temp went to 245/50. I took it to the dealer who said the radiator system developed a bubble so they jacked the car up on one side and drained the system and flushed it. It was under warranty so no big bill. Fast forward to now. We drive it about every two to three weeks but last winter didn't drive it for two months or so during inclement weather. Today, after driving with the a/c on and going slow bumper to bumper for ten minutes, the temp shot up to 248/50. I turned the heater on full blast and drove the 20 miles home. The temp went slowly down to 189 so I turned the heat off and turned the a/c back on for the last 20 minutes home and the temps were normal at 194 to 205. Another bubble maybe? Your thoughts? I will start in tomorrow and let the a/c run at idle and see after 15 minutes or so if the temp starts climbing.

 

[shabby]

Most likely air in the system again, you need these check valves if they weren't install The two check valves for the cooling system..??

 

[Scarletredline2008]

Most likely air in the system again, you need these check valves if they weren't install The two check valves for the cooling system..??

The problem is not in the heater...the heater blows really hot air and is fine. The problem is when the A/C is on, the engine temp shot up but when I turned the heater on, the engine went down to normal temp and then when I turned the a/c back on after the temps were normal...the temp didn't go back up...re-read my post.

 

[Emm]

I think 205 is fine.

 

[Scarletredline2008]

I think 205 is fine.

Emm...re-read the post...205 is normal but that's not what the engine went up to.

 

[Specter]

Same thing happened to me about a year ago. Had them flush and fill the system and no issues since.

 

[Scarletredline2008]

Same thing happened to me about a year ago. Had them flush and fill the system and no issues since.

Yes, I had it done after the first bubble 10 years ago so I guess we went too long letting the car sit over the winter and will have to flush it again.

 

[The_Ghost]

The heater does nothing for these cars. The temp sensor sits right by the heater and when you turn on the heat, it actually appears to run hotter. More then likely your thermostat is old and sticks. What you described is very common when a thermostat has reached its end of life.

 

[Scarletredline2008]

No the problem first surfaced when the car was only two years old and not re-surfaced again. The dealer diagnosed it as a bubble in the system due to not driving the car for three months or so. The temp went down when I turned on the heater. It sounds like another bubble formed.

 

[The_Ghost]

Ok. I'll say it again. Thermostats, sometimes regardless of miles, have a shelf life. Just like tires. Your car is 14 years old. Sometimes mechanical parts fail due to other circumstances, like being soaked in coolant for 14 years. Sometimes they gum up...it happens.

 

[lorennerol]

The dealer diagnosed it as a bubble in the system

I've not experienced or heard of spontaneous bubbles in the cooling system of these cars. Air from incorrect refill procedure? All the time. Air in a sealed system? This is a first.

If there is a leak and the reservoir is low it could pull some air in I guess. Any puddles under the car?

If not, my bet is on the stuck thermostat theory.

 

[Scarletredline2008]

Ok. I'll say it again. Thermostats, sometimes regardless of miles, have a shelf life. Just like tires. Your car is 14 years old. Sometimes mechanical parts fail due to other circumstances, like being soaked in coolant for 14 years. Sometimes they gum up...it happens.

After thinking about it...you're probably right. Easy replacement?

 

[sahein]

T
If my car was overheating, the first thing that I would check for is debris located in front of the radiator and clean it out. The Sky is a bottom breathers like the Corvette. Look at this YouTube video. To save time, skip the first 2/3rds. In some instances I would recommend using engine degreaser and low pressure water to clean.

 

[JohnWR]

After thinking about it...you're probably right. Easy replacement?

The thermostat is not particularly easy to replace.

Was the cooling fan running during the overheat? For that matter it should run whenever the AC is operating. Overheating in traffic but cooling again while driving is a classic fan problem.

The thermostat could have gotten stuck closed and coincidentally un-stuck while driving, but the timing doesn't usually work out that way.

 

[lorennerol]

Was the cooling fan running during the overheat? For that matter it should run whenever the AC is operating.

Valid point. The fan relays in these cars are prone to failure. And the cheap replacements are even more so.