Engine Overheating!!
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Joined: Apr 2007
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From: Fort Walton Beach FL
Engine Overheating!!
BACKGROUND: I was doing some maintenance on one of my pullies that required me to remove the main coolant pipe going into the engine. After I was done with the maintenance, I re-installed the pipe. Natually I lost coolant when I unplugged the hose, so I filled the tank back up. Well, I started the car up, and it immediately began overheating. I did some research on the forum and realized that the coolant system has air inside it and needed to be "burped". I did that and while I was doing that, I realized that my fan was not coming on AT ALL. Even when the engine temps were getting up to 250. 
Not sure if this applies, but my battery also died while I had everything apart. I don't have any codes on the DIC.
Did I accidentally disconnect something to the fan somehow?? I checked the fan, and it spins perfectly by hand. I also checked the fuse, and its fine. I know the fan control module can sometimes crap out, but I find it ironic that it stopped working RIGHT after I worked on the car. The car temps stay around ~200 when driving, mainly do to the air being forced in by forward motion. As soon as I come to a stop, the temps starts to spike!!
Thanks in advance for the help!!!
Not sure if this applies, but my battery also died while I had everything apart. I don't have any codes on the DIC.
Did I accidentally disconnect something to the fan somehow?? I checked the fan, and it spins perfectly by hand. I also checked the fuse, and its fine. I know the fan control module can sometimes crap out, but I find it ironic that it stopped working RIGHT after I worked on the car. The car temps stay around ~200 when driving, mainly do to the air being forced in by forward motion. As soon as I come to a stop, the temps starts to spike!!
Thanks in advance for the help!!!
Last edited by C6_blackhawk; Mar 20, 2008 at 10:24 PM.
Former Vendor
Joined: Mar 2006
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From: SoCal Ca.
Hopeefully someone with some more mechanical knowledge can step in.
I changed my t-stat out and right after the temps rose to about 240 with the fan on. when i noticed I slowly kept the engine rev'd up to 1500 rpm then occasionally 2k (tmp fluctuated up & down during that time). After about 5 minutes the temps dropped to 192.
Hope that helps.
I changed my t-stat out and right after the temps rose to about 240 with the fan on. when i noticed I slowly kept the engine rev'd up to 1500 rpm then occasionally 2k (tmp fluctuated up & down during that time). After about 5 minutes the temps dropped to 192.
Hope that helps.
Thread Starter
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Joined: Apr 2007
Posts: 527
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From: Fort Walton Beach FL
Hopeefully someone with some more mechanical knowledge can step in.
I changed my t-stat out and right after the temps rose to about 240 with the fan on. when i noticed I slowly kept the engine rev'd up to 1500 rpm then occasionally 2k (tmp fluctuated up & down during that time). After about 5 minutes the temps dropped to 192.
Hope that helps.
I changed my t-stat out and right after the temps rose to about 240 with the fan on. when i noticed I slowly kept the engine rev'd up to 1500 rpm then occasionally 2k (tmp fluctuated up & down during that time). After about 5 minutes the temps dropped to 192.
Hope that helps.
Drifting
Joined: Oct 2006
Posts: 1,822
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From: Retired early,everyday is Saturday...Hocking Hills Ohio
Check to see if you can physically move the fan from underneath the car. Small rocks get lodged in the shroud between the ring around the fan and the inside of the shroud and it will not spin at all, I always check mine weekly. 
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From: Fort Walton Beach FL
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Joined: Apr 2007
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From: Fort Walton Beach FL
Update #1. Purge complete. Fan still not working. I decided to "hotwire" the fan directly to the battery to see if the fan motor was bad. The fan turned on like a charm. So somehow the fan is not getting "the memo" to turn on when it should. Any ideas on how I should proceed next?
-Thanks!!
-Thanks!!
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Joined: Apr 2007
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From: Fort Walton Beach FL
Now correct me if I'm wrong, but to purge the system, I'm basically just running the engine with the cap off the overfill tank... and filling it up when needed.... correct??
Safety Car
Joined: Feb 2007
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From: CHOCOWINITY NC
Racer
Joined: Feb 2008
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From: Chandler AZ
Seen this a million times. You definitley have air in your cooling system. You have too much air get it out from just squeezing the hose. You have too options 1. take it to a pro who can flush the sytem under pressure and ensure that no bubbles are present. 2. you can pull the lower hose and drain the system then refill with the cap off and the car on filling it as it runs once it is full put the cap back on and it should be fine. This is not the best way to do it but it does work.
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From: Fort Walton Beach FL
Thanks, I'll quit monkeying around and take it to a professional and have them flush it. Thanks!!
UPDATE: The local oil lube place said that they couldn't flush the system under pressure. I took it home and decided to tinker with it. I found that the ground wire going to the fan was bad. I attached another ground wire, and it works perfectly!!! Thanks for everyones help!! But I'm still going to bring it somewhere to get the radiator flushed under pressure.
UPDATE: The local oil lube place said that they couldn't flush the system under pressure. I took it home and decided to tinker with it. I found that the ground wire going to the fan was bad. I attached another ground wire, and it works perfectly!!! Thanks for everyones help!! But I'm still going to bring it somewhere to get the radiator flushed under pressure.
Last edited by C6_blackhawk; Mar 21, 2008 at 06:35 PM.
Race Director
Joined: Jun 2005
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From: Phila Suburbs 2023 C8 & 2013 650ix
Look, you drove the car and everything was fine, it didn't overheat so air in the system is NOT the problem. It's just a coincidence that whatever system is used to turn the fan on crapped out at the same time you did your pulley work or you knocked a wire loose during your work. There is an fan control module that could have a loose connection but I assume that's where you applied the 12 volts to see if the fan would turn if powered up so that's probably not the problem. But check all the connections to that module that powers the fan. Looks like a trip to the dealer so they can use their scan tool to energize the system and figure out what's broken.
Racer
Joined: Dec 2006
Posts: 250
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From: Florida
Update #1. Purge complete. Fan still not working. I decided to "hotwire" the fan directly to the battery to see if the fan motor was bad. The fan turned on like a charm. So somehow the fan is not getting "the memo" to turn on when it should. Any ideas on how I should proceed next?
-Thanks!!
-Thanks!!
How do you hotwire the fan to the battery or to a fuse in the engine fuse box. Great to know if you need to cool the car at the drags.