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GSR Runs fantastic, no issues. Did 250 miles yesterday, A/C on, no problems. Let car sit two hours. Start it up, in driveway, needle pegged ALL the way to H!
-Radiator, Water pump, OEM all changed 20k miles ago.
This morning, took a look. Coolant is full in radiator. Overflow tank is proper level. 0 leaks in garage.
Doing some youtube research, people said maybe fan not working to check relay. I turned the car on (without starting it), and put the A/C on. Both fans by the radiator immediately turn on. That leads me to believe fan relay is ok and fan motor is ok.
The radiator cap is being a bit finicky, so I figured I will buy a new cap.
If fan is not a problem. Coolant is full. What should I check next, before thinking its T - stat?
My money is on a bad thermostat. You can take it out and boil it to see if it opens and closes.
Replace with OEM (get a new gasket as well) and don't forget to refill and bleed your coolant afterwards.
Agreed. If you're driving, especially at highway speeds, then you don't need a fan to help cool at that point. I'm thinking thermostat as well assuming pump is working.
Most likely the Thermostat but when you replaced the radiator did you properly bleed the radiator?
You should try and bleed it again if you did its possible there is air that needs to come out. Jack the front all the way up as high as possible, take off the radiator cap and put a funnel in to top off the fluid if need be or to catch any fluid bubbling out. Turn the engine on and set the heat in the climate control to full blast on HOT and let the engine idle and keep an eye on the fluid in the funnel and watch for bubbles to come up. Once you hear the fans turn on check the temp gauge to see if its around the middle where it should be for OP temp. Once the engine fans turn on and no more bubbles are present and both hoses are nice and hot and the heater is blowing nice and hot put the cap on and lower the car and take it for a long drive and see what happens.
Agreed. If you're driving, especially at highway speeds, then you don't need a fan to help cool at that point. I'm thinking thermostat as well assuming pump is working.
Most likely the Thermostat but when you replaced the radiator did you properly bleed the radiator?
You should try and bleed it again if you did its possible there is air that needs to come out. Jack the front all the way up as high as possible, take off the radiator cap and put a funnel in to top off the fluid if need be or to catch any fluid bubbling out. Turn the engine on and set the heat in the climate control to full blast on HOT and let the engine idle and keep an eye on the fluid in the funnel and watch for bubbles to come up. Once you hear the fans turn on check the temp gauge to see if its around the middle where it should be for OP temp. Once the engine fans turn on and no more bubbles are present and both hoses are nice and hot and the heater is blowing nice and hot put the cap on and lower the car and take it for a long drive and see what happens.
dealership did radiator and water pump. I didn’t do any bleeding
2) the minute I turned ignition on (cold car), temp gauge goes to almost middle. But it stays there . Fan does not turn on even after 15 min idle.
I switched the relay makes no difference
guage isn’t over heating but also fan not coming on idling
so next question - is it fan motor ? But fan works for a/c but not working for cooling
what would be next steps for trouble shooting ?
Pull the fan switch plug that's on the thermostat and jump the plug! either use a paper clip or a piece of wire with both ends exposed and jump the plug when you plug both leads the fan should automatically turn on, if not you have a bad fan switch sensor or break in the wiring.
Pull the fan switch plug that's on the thermostat and jump the plug! either use a paper clip or a piece of wire with both ends exposed and jump the plug when you plug both leads the fan should automatically turn on, if not you have a bad fan switch sensor or break in the wiring.
thank you
will do that now
quick question - at idle - how long should car run before fan comes on automatically ?
quick question - at idle - how long should car run before fan comes on automatically ?
Thanks
Soon as the needle goes to the middle of the gauge, it usually takes at least 10 mins but not too long.
Originally Posted by 2001GSR4DR
One more question
since the T stat is 10 years old, and I have one oem in hand, should I change that as well, after I figure out the fan ?
Yea man its not much work to replace it, drain the radiator and pull out the thermo and replace it for good measure! Test the sensor by jumping it to see if it triggers the fans to turn on.
If the fans turn on try keeping the fans on with the jumper wire and just go for a spin and see if the fans keep the engine cool in stop and go traffic if so then that's your issue and it might be a break in the wiring causing the fans not to turn on when the engine passes 80*
2) the minute I turned ignition on (cold car), temp gauge goes to almost middle. But it stays there . Fan does not turn on even after 15 min idle.
I switched the relay makes no difference
guage isn’t over heating but also fan not coming on idling
so next question - is it fan motor ? But fan works for a/c but not working for cooling
what would be next steps for trouble shooting ?
Another thing that stands out is this, " 2) the minute I turned ignition on (cold car), temp gauge goes to almost middle. But it stays there . Fan does not turn on even after 15 min idle.
This right here points to either a bad ECT sending unit!, this is the 1 wire ECT plug that's under the distributor! its only function is to send the gauge the current temp. OR its a bad ECT sensor! this is right next to the sending unit plug that is only 1 wire. This ECT sensor is 2 wires, it tells the ECU what the engines temps are so that it can give the correct amount of fuel depending on what the temp is.
Try testing those sensors with a mulitmeter cause with a cold engine the temp gauge should not jump to the middle! it should go up slowly so maybe one or the other sensor is off spec and when the engine gets to OP temp the gauge goes full hot showing it as its overheating when it very well may be just a bad sensor making the gauge show its over heating. Check the manual for trouble shooting those 2 sensors it will show you how to test them using a multimeter, if the values are off spec replace them!
Another thing that stands out is this, " 2) the minute I turned ignition on (cold car), temp gauge goes to almost middle. But it stays there . Fan does not turn on even after 15 min idle.
This right here points to either a bad ECT sending unit!, this is the 1 wire ECT plug that's under the distributor! its only function is to send the gauge the current temp. OR its a bad ECT sensor! this is right next to the sending unit plug that is only 1 wire. This ECT sensor is 2 wires, it tells the ECU what the engines temps are so that it can give the correct amount of fuel depending on what the temp is.
Try testing those sensors with a mulitmeter cause with a cold engine the temp gauge should not jump to the middle! it should go up slowly so maybe one or the other sensor is off spec and when the engine gets to OP temp the gauge goes full hot showing it as its overheating when it very well may be just a bad sensor making the gauge show its over heating.
thank you.
yes so in driveway it “over heated” yesterday per guage so I shut it all down
today (after overnight), sitting when I turned car off, usually temp is hurried in cold. It jumped to “normal” at start up and started moving from there
Soon as the needle goes to the middle of the gauge, it usually takes at least 10 mins but not too long.
Yea man its not much work to replace it, drain the radiator and pull out the thermo and replace it for good measure! Test the sensor by jumping it to see if it triggers the fans to turn on.
If the fans turn on try keeping the fans on with the jumper wire and just go for a spin and see if the fans keep the engine cool in stop and go traffic if so then that's your issue and it might be a break in the wiring causing the fans not to turn on when the engine passes 80*
I have this on my 2000 Civic hatch and its a real nice tool, with this you can check your ECU check engine codes and clear them as well as tons of tools to see the engines functions, so for example if you had this you would open the APP in your phone and you could see what the ECU is reading as far as the engine temps, so lets say on a cold start you have the app open simply put the engine to on and see what the ECT temp is reading when the engine is OFF. If it reads correctly the ECT temp with engine off should read a little less than what the ambient termps are out side. If it shows it hotter than already you know the ECT sensor is malfunctioning. If the ECT temp shows the engine at say 80* which is usually the OP engine temp when its fully warmed up BUT your temp gauge in the car shows the needle at full HOT then you know its the sending unit that's bad.
I have this on my 2000 Civic hatch and its a real nice tool, with this you can check your ECU check engine codes and clear them as well as tons of tools to see the engines functions, so for example if you had this you would open the APP in your phone and you could see what the ECU is reading as far as the engine temps, so lets say on a cold start you have the app open simply put the engine to on and see what the ECT temp is reading when the engine is OFF. If it reads correctly the ECT temp with engine off should read a little less than what the ambient termps are out side. If it shows it hotter than already you know the ECT sensor is malfunctioning. If the ECT temp shows the engine at say 80* which is usually the OP engine temp when its fully warmed up BUT your temp gauge in the car shows the needle at full HOT then you know its the sending unit that's bad.
you we’re right in the money. ECT sensor was culprit. Ordered one
Great! glad we figured it out! these over heating issues can make you go in all directions as far as thinking you have a blown head gasket or bad water pump all which are major over hauls, its always a good thing to go through the easy tests and use any tools you have available for diagnosing which in our case was the OBD scan tool, like I mentioned its a very good tool every one should have! its very similar to having a Hondata S300 V3 Bluetooth option for the Mobile App which is very pricy ! I also have this S300 V3 ECU in my built integra and I want to say the scary thing is the cheap OBD scan tool has more functions than the Hondata mobile APP! but on the lap top its a different story but for the basic sensor displays its very similar and can come in handy in a situation like this.
Great! glad we figured it out! these over heating issues can make you go in all directions as far as thinking you have a blown head gasket or bad water pump all which are major over hauls, its always a good thing to go through the easy tests and use any tools you have available for diagnosing which in our case was the OBD scan tool, like I mentioned its a very good tool every one should have! its very similar to having a Hondata S300 V3 Bluetooth option for the Mobile App which is very pricy ! I also have this S300 V3 ECU in my built integra and I want to say the scary thing is the cheap OBD scan tool has more functions than the Hondata mobile APP! but on the lap top its a different story but for the basic sensor displays its very similar and can come in handy in a situation like this.
Thank you so much. With the new radiator and new oem water pump, was initially thinking thermostat, then fan switch blah blah.
With you catching it that the gauge moved when car started, you nailed it perfectly. My total cost was $28. 18 for the sensor, and I paid 9 for the new radiator cap.
All is well, and just finished another tank of gas. Having fun Owe you big time
Thank you so much. With the new radiator and new oem water pump, was initially thinking thermostat, then fan switch blah blah.
With you catching it that the gauge moved when car started, you nailed it perfectly. My total cost was $28. 18 for the sensor, and I paid 9 for the new radiator cap.
All is well, and just finished another tank of gas. Having fun Owe you big time
Overheating GSR
Owe you big time
