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Discussion Starter · #1 ·
I ran a test with the temp gauge, ( unplugged it from the engine and held it to ground, turn the ignition on and the temp gauge shoots up) I was told that this a faulty temp sensor. Do you have a temp sensor gauge?

I have done all other tests with this overheating problem, I can run the car for about 10-15 minutes it doesn't get to hot, but will after 30 minutes. the hoses are all hot so the coolant is flowing.

when i drive i will go about 3 miles and it gets HOT and i have to get back home. the coolant is boiling out the expansion tank and going all under the car, after cooling down most or all the coolant is drained out of the tank and i have to add more the next time i drive.. Any suggestions? Sound like a faulty temp gauge/ sensor?
 

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Thermostat may still be faulty, cooling system may need flushing, fan may not be working or pressure cap may be faulty.
Or a combination of the above.
 

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Thermostat may still be faulty, cooling system may need flushing, fan may not be working or pressure cap may be faulty.
Or a combination of the above.
I'll add to that a water pump that's not pumping and a possible leak in your coolant tank. Also, have you tried replacing the cap on the tank?

The reason the cooling system is pressurized is to raise the boiling point of the coolant. If the cap is faulty it could be preventing the system from pressurizing.
 

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sounds like radiator needs replacing and I agree with the possibly of the fans not operating?............no mention of fans in the original description.......?
 

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Discussion Starter · #5 ·
fan is hooked to a relay so it runs whenever the car is turned on. Not the problem.

I will buy a cap and see if that's it. I have a new thermostat just haven't gotten to installing it yet. It seems like its going to be tricky. Same thing with the pump.. I can barely see the thing with the AC compressor in the way so it's hard to check the V-belt for damage.

I installed the relay for the fan and it worked for about a week, now the car will overheat in no time just driving to the store and back (2-3 miles)

The tank has small white stretch mark, maybe cracks on it from the tank expanding from being so hot. i'll order a tank as well just to have a new one.. just need to know about the temp gauge sender. could it cause overheating?
 

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You grounded the sensor wire and the gauge went to full hot, right? then the gauge is likely work ok. You say it shows the engine is getting hot, barring any evidence to the contrary, I would take the gauge at its word. You haven't said if the radiator itself is hot all over or if it has cool spots. My guess would be you need a new radiator and may be a headgasket or will soon if you keep driveing it with this problem.
 

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A temperature gauge sender cannot cause over heating.
Your car has an issue with heat removal from the coolant.
The primary way that heat is removed from the coolant is the radiator.
 

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Any suggestions? Sound like a faulty temp gauge/ sensor?
NO it does not , It sounds exactly the opposite ,

As suggested in the replies above , you have a problem with your cooling system , not the gauge .

you say all hoses are hot , what about the Bottom radiator hose ?
 

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I ran a test with the temp gauge, ( unplugged it from the engine and held it to ground, turn the ignition on and the temp gauge shoots up) I was told that this a faulty temp sensor.
When you ground the sensor wire to the gauge the needle will show max. This is what it's meant to do. There is nothing wrong with the gauge. The fault lies elsewhere. A faulty gauge will not affect anything on the engine. It will only affect the gauge reading. It could be clogged rad (flushing won't cure this), faulty pump or thermostat (although you say it's circulating). I wouldn't rule out headgasket.

A
 

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Rad's definately the key, as I would suggest the thermostat would be opening even at max temp, they usually fail by opening too early or staying open, a rare occurence to stay shut, but with how hot yours gets so quickly, there's no flow anywhere
remove bottom hose (left remove rad drain plug(right)
remove top hose, and remove rad temp sensor, and see what comes out?? when bottom hose and drain plug loosesned/removed, then put a hose in the top hose hole and then alternate to the temp hole and see how much other stuff comes out and when(if) it starts to get clear, then you might stand a chance of car runnning without overheating, but a new one sounds in order anyway, as my flushing 'words' though will only give you temporary freedom from heat probs, but will certainly stop you blowing a gasket .
when car is running put a screwdriver on the body of the w/pump and then next to your ear, if it's noisy it could have failed internally, as some non origanal type of w/p impellars are thin steel and rot out etc, but if a bearing had gone the water would be pouring out the back all the time,and when you drain the rad fit a new thermostat anyway
 

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Possible PO used stop leak in radiator or Zerex coolant? Were you able to check the face of the radiator at all after hoses were hot? should be the same temp all over (engine off, fan relay fuse pulled).
 

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just another thought, if you Rad sensor is surrounded with crap or no good, it would not be operating the fan to help cool the rad even if water was flowing, so possible rad sensor as well, but see if the FLUSH works first before any expense
 

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I have suggested above the head gasket may have failed. Do you get white smoke out of the exhaust or bubbles in the coolant reservoir when the engine is running? These are classic HG symptoms.

It is unlikely to be your fan because you say it overheats when you are driving. The fan normally only comes on when you are stationary and there is no air flow through the radiator. In my experience flushing never, ever, cleared a clogged radiator. Don't waste your money. You could check water flow by observing the flow across the reservoir when the engine is revved with cap removed on a warm engine. This flow comes from the small hose at the front of the reservoir. This comes from the rad and is intended to purge any air in the rad. If you can see this flow, the water is circulating, but not necessarily through the radiator.
 

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Discussion Starter · #14 ·
I replaced the thermostat (the old one was so gunked and corroded) replaced the bottom and top radiator hoses one was cracked in the middle, cleaned out the AIC with carb cleaner, flushed the system and I also cleaned around the engine with degreaser & wiped a lot of build up off the temp gauge sensor and around the engine. Took about 3-4 hours of labor for everything( not to bad) It's fixed though and running great. Now to just give her some TLC and do some minor body work and interior.

Thanks everyone for the help;ol;;ol;;ol;;ol;;ol;;ol;;ol;



You grounded the sensor wire and the gauge went to full hot, right? then the gauge is likely work ok. You say it shows the engine is getting hot, barring any evidence to the contrary, I would take the gauge at its word. You haven't said if the radiator itself is hot all over or if it has cool spots. My guess would be you need a new radiator and may be a headgasket or will soon if you keep driveing it with this problem.
A temperature gauge sender cannot cause over heating.
Your car has an issue with heat removal from the coolant.
The primary way that heat is removed from the coolant is the radiator.
NO it does not , It sounds exactly the opposite ,

As suggested in the replies above , you have a problem with your cooling system , not the gauge .

you say all hoses are hot , what about the Bottom radiator hose ?
I'll add to that a water pump that's not pumping and a possible leak in your coolant tank. Also, have you tried replacing the cap on the tank?

The reason the cooling system is pressurized is to raise the boiling point of the coolant. If the cap is faulty it could be preventing the system from pressurizing.
Rad's definately the key, as I would suggest the thermostat would be opening even at max temp, they usually fail by opening too early or staying open, a rare occurence to stay shut, but with how hot yours gets so quickly, there's no flow anywhere
remove bottom hose (left remove rad drain plug(right)
remove top hose, and remove rad temp sensor, and see what comes out?? when bottom hose and drain plug loosesned/removed, then put a hose in the top hose hole and then alternate to the temp hole and see how much other stuff comes out and when(if) it starts to get clear, then you might stand a chance of car runnning without overheating, but a new one sounds in order anyway, as my flushing 'words' though will only give you temporary freedom from heat probs, but will certainly stop you blowing a gasket .
when car is running put a screwdriver on the body of the w/pump and then next to your ear, if it's noisy it could have failed internally, as some non origanal type of w/p impellars are thin steel and rot out etc, but if a bearing had gone the water would be pouring out the back all the time,and when you drain the rad fit a new thermostat anyway
I have suggested above the head gasket may have failed. Do you get white smoke out of the exhaust or bubbles in the coolant reservoir when the engine is running? These are classic HG symptoms.

It is unlikely to be your fan because you say it overheats when you are driving. The fan normally only comes on when you are stationary and there is no air flow through the radiator. In my experience flushing never, ever, cleared a clogged radiator. Don't waste your money. You could check water flow by observing the flow across the reservoir when the engine is revved with cap removed on a warm engine. This flow comes from the small hose at the front of the reservoir. This comes from the rad and is intended to purge any air in the rad. If you can see this flow, the water is circulating, but not necessarily through the radiator.
 

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Good job! ;ol;
 
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