Running hot.. what could this be?
12-22-2004, 02:50 AM
#1
Burning Brakes
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Running hot.. what could this be?
OK -- I've just replaced the radiator, thermostat, and a few coolant hoses... then bled the hell out of the system to ensure that no air remains. The heat blows hot, as it should, with no "gurgly" noises. Coolant seems to be flowing to and fro quite as it should. Fans come on as they should. The car idles and runs nicely.
However, the car still runs sort of hot. It does not overheat - it goes to the "second line" on the temp guage and just sits there. What could this possibly be?
I'm dumbfounded, frustrated, confused..
However, the car still runs sort of hot. It does not overheat - it goes to the "second line" on the temp guage and just sits there. What could this possibly be?
I'm dumbfounded, frustrated, confused..
12-22-2004, 02:54 AM
#2
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Welcome to the club. I just went through this (since june actually) and had PLENTY of parts changed. Have you checked the thermoswitch. It could be going bad. Sounds just like mine. Also, my temp. guage was no good as well.
12-22-2004, 03:01 AM
#3
Burning Brakes
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Thermoswitch is also relatively new.. it has maybe a few thousand miles on it - fans come on as they should.
Guage could be an issue but I am find that somewhat hard to believe?
Guage could be an issue but I am find that somewhat hard to believe?
12-22-2004, 03:10 AM
#4
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You could check/replace the gauge sending unit (golden looking piece next to the DME temp sensor).
Second white? don't you mean third white befor the red line???
You could try this for checking:http://www.clarks-garage.com/shop-ma...19.htm#coolant
Second white? don't you mean third white befor the red line???
You could try this for checking:http://www.clarks-garage.com/shop-ma...19.htm#coolant
12-22-2004, 08:41 AM
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Double check the coolant for air. I had this problem in my S2. Even though the system was bled, if I recall it took three or four times to get it all out. Also, did you install the thermostat switch with the lower setting? Is the secondary fan coming on?
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12-22-2004, 10:36 AM
#8
Three Wheelin'
Schlag:
The main thing you want to keep in mind is that when ever you make any changes to the cooling or electrical systems chances are the temperature gage will indicate differently than it did before the changes were made.
This includes seemingly unrelated things like changing blubs in the gage cluster, or cleaning grounds.
With that in mind, if you are condfident that the system is properly filled and bled, and that other components like fans, t-stat, and so forth are functioning properly, then what you need to do is keep track of where the temp gage indicates under various driving condidtions.
For example on my '87NA the temp gage stays at or just below the middle mark while cruising, but it will climb to the next mark when sitting at idle. And unlike my old '84, once the fans come on, they typically do not shut off until after the engine is shut down.
My '86 turbo is entirely different. During cruise, the temp gage indicates about where the gage in the NA indicates, but the 951 gage climbs to the third mark before the fans come on. Coincidentally, this is how my '84 ran.
During cruise the '84's temp gage would indicate at the first mark. When idling, the temp gage would climb to the third mark and the fans would come on. Once the temp got back towards the lower mark the fans would turn off.
What I suspect is the NA has a low temp fan switch while the switch in the 951 is "stock."
What all three cars had in common is that the temp gage indications are repeatable. By this I mean that under a given set of conditions (stop-n-go traffic, city driving, highway driving, etc.) the temp gage always does the same thing.
In addition to keeping track of the temp gage you need to keep track of the coolant level (Coolant level should be between the MAX and MIN marks on the expansion tank when the engine is HOT.), oil consumption, fuel consumption, and spark plug condition.
The main thing you want to keep in mind is that when ever you make any changes to the cooling or electrical systems chances are the temperature gage will indicate differently than it did before the changes were made.
This includes seemingly unrelated things like changing blubs in the gage cluster, or cleaning grounds.
With that in mind, if you are condfident that the system is properly filled and bled, and that other components like fans, t-stat, and so forth are functioning properly, then what you need to do is keep track of where the temp gage indicates under various driving condidtions.
For example on my '87NA the temp gage stays at or just below the middle mark while cruising, but it will climb to the next mark when sitting at idle. And unlike my old '84, once the fans come on, they typically do not shut off until after the engine is shut down.
My '86 turbo is entirely different. During cruise, the temp gage indicates about where the gage in the NA indicates, but the 951 gage climbs to the third mark before the fans come on. Coincidentally, this is how my '84 ran.
During cruise the '84's temp gage would indicate at the first mark. When idling, the temp gage would climb to the third mark and the fans would come on. Once the temp got back towards the lower mark the fans would turn off.
What I suspect is the NA has a low temp fan switch while the switch in the 951 is "stock."
What all three cars had in common is that the temp gage indications are repeatable. By this I mean that under a given set of conditions (stop-n-go traffic, city driving, highway driving, etc.) the temp gage always does the same thing.
In addition to keeping track of the temp gage you need to keep track of the coolant level (Coolant level should be between the MAX and MIN marks on the expansion tank when the engine is HOT.), oil consumption, fuel consumption, and spark plug condition.
12-22-2004, 10:59 AM
#9
Burning Brakes
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Originally Posted by Charlotte944
Schlag:
The main thing you want to keep in mind is that when ever you make any changes to the cooling or electrical systems chances are the temperature gage will indicate differently than it did before the changes were made.
This includes seemingly unrelated things like changing blubs in the gage cluster, or cleaning grounds.
With that in mind, if you are condfident that the system is properly filled and bled, and that other components like fans, t-stat, and so forth are functioning properly, then what you need to do is keep track of where the temp gage indicates under various driving condidtions.
For example on my '87NA the temp gage stays at or just below the middle mark while cruising, but it will climb to the next mark when sitting at idle. And unlike my old '84, once the fans come on, they typically do not shut off until after the engine is shut down.
My '86 turbo is entirely different. During cruise, the temp gage indicates about where the gage in the NA indicates, but the 951 gage climbs to the third mark before the fans come on. Coincidentally, this is how my '84 ran.
During cruise the '84's temp gage would indicate at the first mark. When idling, the temp gage would climb to the third mark and the fans would come on. Once the temp got back towards the lower mark the fans would turn off.
What I suspect is the NA has a low temp fan switch while the switch in the 951 is "stock."
What all three cars had in common is that the temp gage indications are repeatable. By this I mean that under a given set of conditions (stop-n-go traffic, city driving, highway driving, etc.) the temp gage always does the same thing.
In addition to keeping track of the temp gage you need to keep track of the coolant level (Coolant level should be between the MAX and MIN marks on the expansion tank when the engine is HOT.), oil consumption, fuel consumption, and spark plug condition.
The main thing you want to keep in mind is that when ever you make any changes to the cooling or electrical systems chances are the temperature gage will indicate differently than it did before the changes were made.
This includes seemingly unrelated things like changing blubs in the gage cluster, or cleaning grounds.
With that in mind, if you are condfident that the system is properly filled and bled, and that other components like fans, t-stat, and so forth are functioning properly, then what you need to do is keep track of where the temp gage indicates under various driving condidtions.
For example on my '87NA the temp gage stays at or just below the middle mark while cruising, but it will climb to the next mark when sitting at idle. And unlike my old '84, once the fans come on, they typically do not shut off until after the engine is shut down.
My '86 turbo is entirely different. During cruise, the temp gage indicates about where the gage in the NA indicates, but the 951 gage climbs to the third mark before the fans come on. Coincidentally, this is how my '84 ran.
During cruise the '84's temp gage would indicate at the first mark. When idling, the temp gage would climb to the third mark and the fans would come on. Once the temp got back towards the lower mark the fans would turn off.
What I suspect is the NA has a low temp fan switch while the switch in the 951 is "stock."
What all three cars had in common is that the temp gage indications are repeatable. By this I mean that under a given set of conditions (stop-n-go traffic, city driving, highway driving, etc.) the temp gage always does the same thing.
In addition to keeping track of the temp gage you need to keep track of the coolant level (Coolant level should be between the MAX and MIN marks on the expansion tank when the engine is HOT.), oil consumption, fuel consumption, and spark plug condition.
I suppose that's not abnormal, but it's higher than it used to be and considering the ambient temp was below freezing I would hope for it to linger around the first sliver or second notch.
12-22-2004, 12:32 PM
#11
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Originally Posted by pete944
If possible, remove the thermostat and check to see at what temperature it opens. I had 2 new ones that were bad right out of the box.
12-22-2004, 12:33 PM
#12
944s and especially 951s are notorious for false temp readings
I had the same problem with my old 951 , did everything and the gauge still read hot, I used a temp reading gun around the water pump area and the reading was around 180/190 but the gauge was giving me 230+ it all comes down to a bad wire connection in the temp gauge circut.Check the sender and contacts, I am pretty sure that where your problem lies.
I had the same problem with my old 951 , did everything and the gauge still read hot, I used a temp reading gun around the water pump area and the reading was around 180/190 but the gauge was giving me 230+ it all comes down to a bad wire connection in the temp gauge circut.Check the sender and contacts, I am pretty sure that where your problem lies.
12-22-2004, 12:36 PM
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What line are you referring to? Third white = up top right under red, second white = the middle one, bottom white is of course first one. The middle white one is only 50 degree C, top white is 100 degrees C, resd is 120 or something.
So which line is it?
Between the middle and top one is fairly normal. It can take a while to bleed all the air out, and doesnt take much air to bugger things up. Isnt unheard of to have an out of box failure on a thermostat.... Happened to me.
So which line is it?
Between the middle and top one is fairly normal. It can take a while to bleed all the air out, and doesnt take much air to bugger things up. Isnt unheard of to have an out of box failure on a thermostat.... Happened to me.
12-22-2004, 12:40 PM
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Does the gauge bounce around or does it just sit there and not move whatsoever? After doing a lot of cooling system maintenance I had a problem where my gauge seemed to go to the same line you are talking about, but it bounced around somewhat when I went over bumps in the road. If it does bounce around (which it doesn't seem like it is, just making a suggestion) it is probably the ground for the gauge.
12-23-2004, 12:41 AM
#15
Burning Brakes
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Originally Posted by badass951
Does the gauge bounce around or does it just sit there and not move whatsoever? After doing a lot of cooling system maintenance I had a problem where my gauge seemed to go to the same line you are talking about, but it bounced around somewhat when I went over bumps in the road. If it does bounce around (which it doesn't seem like it is, just making a suggestion) it is probably the ground for the gauge.