96 Buick Regal 3.8 Radiator Fans not working properly.
#1
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Hello, I decided to join the forum to try to keep my wife'* 96 Buick Regal from ending up in a junk yard.
The issue I am having currently with the car is that the radiator fans do not seem to be functioning properly.
A little history on the car first. Some time ago, roughly a year and a half, the 90 degree plastic coolant elbow blew out while she was driving on the highway. The car overheated on her and shut off. She then drove it home, stopping about 5 times due to overheating. I think she was about 4 miles from the house, about 3 of that non highway. When looked at it, there was no remaining coolant in the system. Praying that nothing warped or cracked, I replaced the elbow with a new plastic one. After refilling it, the car started and the coolant circulated. Everything seemed fine. No leaking coolant into the oil, no external leaks that I could detect.
About 6 months after that while my wife and I were driving to an event, I noticed the dash temp gauge start to slowly climb. When the temp reach over the 3/4 mark, I pulled over into a parking lot and shut the car off. The elbow had again blown out. I replaced that one with an all aluminum version, went to a buick dealer and purchased their o-rings to install it with. The car has been fine considering the close calls. The only permanent issue that I have seen so far is the low coolant dash indicator comes on and off at randomly during a drive, and sometimes is on constantly but really dim. I believe the sensor was fried in the overheating.
Because of all this, I monitor the temp gauge every time I drive it. This week I let my wife borrow my car for a trip out of town so I had some time with the buick. I noticed the temp gauge was climbing really slowly past what it normally sits at (around 1/4 mark) while in stopped traffic. I know some rise in temp when coming to a stop or in stopped traffic is normal, but this continued to rise past the halfway mark and up the 3/4 mark. the temp will drop again when the car is moving.
After researching on the topic through the internet, I have tried a few things to test the fans to make sure they are functioning. The first test was to drive the car till the temp reached 3/4 and pulled into a parking lot, open the hood and see the primary fan was not running. the secondary fan was also not running. I know the secondary fan comes on after the primary and at a higher temp. I will have to admit that I do not know the temp ranges of the gauge since there are only lines and not numbers. The second test was to turn on the A/C unit. Secondary fan will start and run, then after a few moments the primary fan will start. The third test was to unplug the Temp sensor, both fans kick on about 3 seconds after the car is started and continue to run. When I plugged the sensor back in and restarted the car, both fans immediately started and ran for about a minute before shutting off.
I am by no means a great mechanic but enjoy trying to do most repairs on my own when I have the time. I can stumble my way through most repairs if I have good directions to follow so any help would be appreciated.
The issue I am having currently with the car is that the radiator fans do not seem to be functioning properly.
A little history on the car first. Some time ago, roughly a year and a half, the 90 degree plastic coolant elbow blew out while she was driving on the highway. The car overheated on her and shut off. She then drove it home, stopping about 5 times due to overheating. I think she was about 4 miles from the house, about 3 of that non highway. When looked at it, there was no remaining coolant in the system. Praying that nothing warped or cracked, I replaced the elbow with a new plastic one. After refilling it, the car started and the coolant circulated. Everything seemed fine. No leaking coolant into the oil, no external leaks that I could detect.
About 6 months after that while my wife and I were driving to an event, I noticed the dash temp gauge start to slowly climb. When the temp reach over the 3/4 mark, I pulled over into a parking lot and shut the car off. The elbow had again blown out. I replaced that one with an all aluminum version, went to a buick dealer and purchased their o-rings to install it with. The car has been fine considering the close calls. The only permanent issue that I have seen so far is the low coolant dash indicator comes on and off at randomly during a drive, and sometimes is on constantly but really dim. I believe the sensor was fried in the overheating.
Because of all this, I monitor the temp gauge every time I drive it. This week I let my wife borrow my car for a trip out of town so I had some time with the buick. I noticed the temp gauge was climbing really slowly past what it normally sits at (around 1/4 mark) while in stopped traffic. I know some rise in temp when coming to a stop or in stopped traffic is normal, but this continued to rise past the halfway mark and up the 3/4 mark. the temp will drop again when the car is moving.
After researching on the topic through the internet, I have tried a few things to test the fans to make sure they are functioning. The first test was to drive the car till the temp reached 3/4 and pulled into a parking lot, open the hood and see the primary fan was not running. the secondary fan was also not running. I know the secondary fan comes on after the primary and at a higher temp. I will have to admit that I do not know the temp ranges of the gauge since there are only lines and not numbers. The second test was to turn on the A/C unit. Secondary fan will start and run, then after a few moments the primary fan will start. The third test was to unplug the Temp sensor, both fans kick on about 3 seconds after the car is started and continue to run. When I plugged the sensor back in and restarted the car, both fans immediately started and ran for about a minute before shutting off.
I am by no means a great mechanic but enjoy trying to do most repairs on my own when I have the time. I can stumble my way through most repairs if I have good directions to follow so any help would be appreciated.
Last edited by Tallboy; 07-01-2014 at 03:02 PM.
#2
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For as long as I've been on this forum, and the number of times I've seen these engines over heat here, none of them I can think of have ever had permanent damage done to the engine.
From what you have said, it appears that your fans are working fine. These fans are PROGRAMMED at the PCM to turn on around 212* and HIGH at 226*
I've always hated gauges with "tick" marks and no numbers. Best way to tell, connect a scanner to the car and "see" what the PCM is seeing.
From what you have said, it appears that your fans are working fine. These fans are PROGRAMMED at the PCM to turn on around 212* and HIGH at 226*
I've always hated gauges with "tick" marks and no numbers. Best way to tell, connect a scanner to the car and "see" what the PCM is seeing.
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#3
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you really only need numbers when troubleshooting, it only really matters that what ever line it normally is at it stays there. but in this case it seems the ect may be giving the pcm and incorrect indication. if you turn on the ac and both come on you know the pcm and relays are good. like he said only way to know for sure is check the temp with a scanner.
as far as the coolant level gauge the sensor is normally in the tank of the rad. sounds like you have a bad one or the wires or plug are messed up
as far as the coolant level gauge the sensor is normally in the tank of the rad. sounds like you have a bad one or the wires or plug are messed up
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Tallboy (07-02-2014)
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I had a chance today to do as you said and hooked the car to get some numbers. The numbers and events I received are:
180 degrees F. at the mark that the vehicle normal operates at
at 212-218 degres F. No fans are active
at 223-225 degrees F. The passenger side fans swtiches on
back to 214-216 degrees F. The passenger side fan switches off.
I cycled the temp up and down while parked. The only time the drivers side fan activates is when I have the A/C on. When the engine is around 220 degrees and I turn on the A/C, the passenger fan starts first. Then the drivers side starts about 10 seconds after that.
Does this sound like I need to replace the ECT?
As for the coolant level sensor, I never got around to changing it out at the time when the elbow blew the second time. One of those get it back on the road asap jobs
. It looks fairly simple to change out with just a clip and a pull.
180 degrees F. at the mark that the vehicle normal operates at
at 212-218 degres F. No fans are active
at 223-225 degrees F. The passenger side fans swtiches on
back to 214-216 degrees F. The passenger side fan switches off.
I cycled the temp up and down while parked. The only time the drivers side fan activates is when I have the A/C on. When the engine is around 220 degrees and I turn on the A/C, the passenger fan starts first. Then the drivers side starts about 10 seconds after that.
Does this sound like I need to replace the ECT?
As for the coolant level sensor, I never got around to changing it out at the time when the elbow blew the second time. One of those get it back on the road asap jobs
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Last edited by Tallboy; 07-02-2014 at 02:43 PM.
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The low speed is a single fan. High speed is both fans on together.
Your software may be programed a few degrees different than mine. I was looking at my PCM file using a programmer.
Either way, your fans are working correctly.
Your software may be programed a few degrees different than mine. I was looking at my PCM file using a programmer.
Either way, your fans are working correctly.
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Tallboy (07-02-2014)
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Thank goodness. I guess since the blown elbow I've been anxious about her car breaking down on her so I get paranoid when it starts acting weird or unusual. Thank you for your help with this false alarm.
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No worries. We see people in here all the time concerned with fans not turning on.
Like with everyone else that'* handy with a wrench, I always recommend that they take the 195* t-stat out and put a 180* in during the summer time. It does help keep the temps down.
Like with everyone else that'* handy with a wrench, I always recommend that they take the 195* t-stat out and put a 180* in during the summer time. It does help keep the temps down.
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