ECM Temperature Sensor?
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ECM Temperature Sensor?
Hi all, I'm a new member....I recently purchased a 1995 Corvette Convertible with 25k original miles. The car would run hot when I'm stopped. I noticed the electric fan wasn't working. I had a friend of mine run some tests and it was determined the fan does work (when set up on there testing computer) fan actually turned on, relays are working. He said it was most likely the temperature sensor (ECM). Has anyone ever had this replaced and is it a big job? Or any info you guys can provide me would help a great deal. I didn't know if I should just take it to Chevrolet dealer as my wife wants me to or if it s something simple a garage mechanic can fix? All your thoughts are appreciated...Thanks
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From: WV
Hi all, I'm a new member....I recently purchased a 1995 Corvette Convertible with 25k original miles. The car would run hot when I'm stopped. I noticed the electric fan wasn't working. I had a friend of mine run some tests and it was determined the fan does work (when set up on there testing computer) fan actually turned on, relays are working. He said it was most likely the temperature sensor (ECM). Has anyone ever had this replaced and is it a big job? Or any info you guys can provide me would help a great deal. I didn't know if I should just take it to Chevrolet dealer as my wife wants me to or if it s something simple a garage mechanic can fix? All your thoughts are appreciated...Thanks
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I let the temp run up to 225 and the fan still did not come on. When the diagnostic tool was attached he automatically turned on the fan using the tool so I know the fan works.
Last edited by TTShab; Apr 21, 2014 at 02:28 PM.
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Hi all, I'm a new member....I recently purchased a 1995 Corvette Convertible with 25k original miles. The car would run hot when I'm stopped. I noticed the electric fan wasn't working. I had a friend of mine run some tests and it was determined the fan does work (when set up on there testing computer) fan actually turned on, relays are working. He said it was most likely the temperature sensor (ECM). Has anyone ever had this replaced and is it a big job? Or any info you guys can provide me would help a great deal. I didn't know if I should just take it to Chevrolet dealer as my wife wants me to or if it s something simple a garage mechanic can fix? All your thoughts are appreciated...Thanks
Don't go by the analog temp gauge, as it will make you think it is way too hot.
It does not have a linear scale on the dial, and unless the needle is into the "shaded" area the car isn't overheating.
Use the digital temp gauge and see what that reads.
You very well may not have anything that needs fixing yet.
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My digital was up to 225, analog was about the same. I was afraid to let it get any hotter. I know the car mostly sat in a garage for 2 years and was proven to only had driven 50 miles on it from the time it was serviced as per mileage and dated receipts
Last edited by TTShab; Apr 21, 2014 at 02:28 PM.
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The sensor in the passenger side head is for the anolog gauge..You have one in the waterpump that goes to the ECM...Make sure you change the coolant and all other fluids if the car has been sitting that long..Having a car sit for long periods of time is the worst thing for them.....WW
Last edited by WW7; Apr 21, 2014 at 02:04 PM.
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Yeah I believe its the water pump one that they want to change. Looks hard to get to and expensive. I was going to have all the fluids changed, but now I have this damn fan problem.. Does that ECM Temp Sensor have anything to do with the fan?
Last edited by TTShab; Apr 21, 2014 at 02:05 PM.
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Hi all, I'm a new member....I recently purchased a 1995 Corvette Convertible with 25k original miles. The car would run hot when I'm stopped. I noticed the electric fan wasn't working. I had a friend of mine run some tests and it was determined the fan does work (when set up on there testing computer) fan actually turned on, relays are working. He said it was most likely the temperature sensor (ECM). Has anyone ever had this replaced and is it a big job? Or any info you guys can provide me would help a great deal. I didn't know if I should just take it to Chevrolet dealer as my wife wants me to or if it s something simple a garage mechanic can fix? All your thoughts are appreciated...Thanks
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Im not positive, but I believe the ECM turns the fan on in the LT1 cars.. Need someone else to verify this....
Another thing that could be causing the overheating is in the 2 years it sat , air could have gotten into the cooling system and you may have to burp the system to get it out......WW
Another thing that could be causing the overheating is in the 2 years it sat , air could have gotten into the cooling system and you may have to burp the system to get it out......WW
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WOOT!!! I have great news!!! I watched the Temperature Gauge go up to 228 degrees. and all of a sudden the fan kicked on and lowered it back down to 215 until I shut it off. WOW ...You guys rock thank you for the advice!!!!! All that worry for nothing.... I would never have let the car get that hot if it wasn't for you guys telling me they run hot....Thanks again!!!!
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WOOT!!! I have great news!!! I watched the Temperature Gauge go up to 228 degrees. and all of a sudden the fan kicked on and lowered it back down to 215 until I shut it off. WOW ...You guys rock thank you for the advice!!!!! All that worry for nothing.... I would never have let the car get that hot if it wasn't for you guys telling me they run hot....Thanks again!!!!
Now go change that antifreeze before it screws something up....
..You will need to burp the system, that will be lesson 2...There are tutorials on this site, telling how to do this and many more things on your car..Find them and use them.......If you depend on a mechanic to do everything on the car, you will be broke in a short time...WW
Last edited by WW7; Apr 21, 2014 at 02:51 PM.
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Another thing to try, is turn on the A/C. If your A/C is in operating, that will cause the cooling fans to run.
Also as hard as it is for most to understand, 225°F - 235°F is not really that hot.
GM says to shut it down if the temp reaches 260°F.
With the proper coolant mix and pressure, the boiling point is up close to 265°F
Normal operating temps for an LT1/LT4
Sitting at stop lights in stop and go traffic: 217°F - 235°F
Moving at any speed above 35 mph: 190°F - 200°F
Last edited by RollaMo-LT4; Apr 21, 2014 at 03:32 PM. Reason: typo
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225°F is probably hot enough to cause the fans to come on.
Another thing to try, is turn on the A/C. If your A/C is in operating, that will cause the cooling fans to run.
Also as hard as it is for most to understand, 225°F - 235°F is not really that hot.
GM says to shut it down if the temp reaches 260°F.
With the proper coolant mix and pressure, the boiling point is up close to 265°F
Normal operating temps for an LT1/LT4
Sitting at stop lights in stop and go traffic: 217°F - 235°F
Moving at any speed above 35 mph: 190°F - 200°F
Another thing to try, is turn on the A/C. If your A/C is in operating, that will cause the cooling fans to run.
Also as hard as it is for most to understand, 225°F - 235°F is not really that hot.
GM says to shut it down if the temp reaches 260°F.
With the proper coolant mix and pressure, the boiling point is up close to 265°F
Normal operating temps for an LT1/LT4
Sitting at stop lights in stop and go traffic: 217°F - 235°F
Moving at any speed above 35 mph: 190°F - 200°F
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225°F is probably "NOT" hot enough to cause the fans to come on.
Another thing to try, is turn on the A/C. If your A/C is in operating, that will cause the cooling fans to run.
Also as hard as it is for most to understand, 225°F - 235°F is not really that hot.
GM says to shut it down if the temp reaches 260°F.
With the proper coolant mix and pressure, the boiling point is up close to 265°F
Normal operating temps for an LT1/LT4
Sitting at stop lights in stop and go traffic: 217°F - 235°F
Moving at any speed above 35 mph: 190°F - 200°F
Another thing to try, is turn on the A/C. If your A/C is in operating, that will cause the cooling fans to run.
Also as hard as it is for most to understand, 225°F - 235°F is not really that hot.
GM says to shut it down if the temp reaches 260°F.
With the proper coolant mix and pressure, the boiling point is up close to 265°F
Normal operating temps for an LT1/LT4
Sitting at stop lights in stop and go traffic: 217°F - 235°F
Moving at any speed above 35 mph: 190°F - 200°F
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From: WV
...WW
Last edited by WW7; Apr 21, 2014 at 07:01 PM.
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You can't say spun bearings due to overheating without listing the temps that caused the issue.
If you get "spun bearings" running at any temps below 240°F, you have something else wrong.
As I mentioned earlier, 225°F - 235°F is not at all that hot on modern engines.
They will run for over 100,00 miles running within the factory temp specs.