95 chevy lumina fans don't work

[jeffcoslacker]

I guess the other question we haven't aksed yet is what does it do when you drive it?

As long as you're moving, the fans are not needed...if it still goes hot when moving down the road, the fans have nothing to do with it...

[darin00]

when its starts to overheat the light will come on and the fan will kick on and the gauge will back down in between the normal and the red line.

[j cAT]

Originally Posted by darin00

when its starts to overheat the light will come on and the fan will kick on and the gauge will back down in between the normal and the red line.

I then would like to know what temperature sensor did you replace ? ... the sensor at thermostat is the one that tells ecm to turn on fans.....that is the sensor that has to be bad....did you replace sensor at thermostat? when it gets to the overheat condition is the coolant boiling.. is the recover tank above full hot .....from cold to normal temp the recovery bottle should rise from cold level mark to hot level mark does the coolant rise like this? if not replace the coolant cap....

IF THE VEHICLE IS NOT MOVING THE FANS WILL COME ON EVENTUALLY , BUT NOT WHEN YOU GET A WARNING LIGHT THAT INDICATES OVERHEATING....these sensors are resistors remove both sensors measure resistance both should be the same resistance..... then place in boiling water again both should read the same resistance......can you do that.....?

[j cAT]

Originally Posted by darin00

when its starts to overheat the light will come on and the fan will kick on and the gauge will back down in between the normal and the red line.

before starting engine the resistance of the sensors ect and cts are at 40deg f resistance of 7300 ohms , then when vehicle is at normal temp of 195deg f the resistance should be 240ohms...they don't have to be removed just measure in place with connector removed....now if at 195deg the sensor reads higher ohms than this amount , then the ecm will think the the temp is lower...as the higher the resistance the lower the temp...this I believe is why fans come on too late or does it ?

[spdfrk1990]

I think my ECT might be bad but I have some questions. Ok my primary fan seems to not be coming on it gets hotter then normal now when I stop. It will turn on tho if I engage the ac compressor I need to check it again though. My coolant is full also. Anyway if the ect was bad wouldnt that keep the motor from going into closed loop also and throw a code or is it possible it just throwing false info the the ecu and not throwing a code?? What other coolant sensors does the car have?

Thanks,
John

[j cAT]

Originally Posted by spdfrk1990

I think my ECT might be bad but I have some questions. Ok my primary fan seems to not be coming on it gets hotter then normal now when I stop. It will turn on tho if I engage the ac compressor I need to check it again though. My coolant is full also. Anyway if the ect was bad wouldnt that keep the motor from going into closed loop also and throw a code or is it possible it just throwing false info the the ecu and not throwing a code?? What other coolant sensors does the car have?

Thanks,
John

one sensor ECT is near the thermostat this is the fan computer sensor, I don't know were your dash temp sensor is located you will have to find out..... anyway both should read the same resistance ... if not ....then at certain temps you will get a specific resistance , ,, if incorrect fans may not come on correctly....as well as other problems like if computer thinks ....... its -40deg out engine may not start correctly.....if the connector or wiring is bad then it will throw a code if it reads the wrong temp no code...

[spdfrk1990]

Originally Posted by j cAT

one sensor ECT is near the thermostat this is the fan computer sensor, I don't know were your dash temp sensor is located you will have to find out..... anyway both should read the same resistance ... if not ....then at certain temps you will get a specific resistance , ,, if incorrect fans may not come on correctly....as well as other problems like if computer thinks ....... its -40deg out engine may not start correctly.....if the connector or wiring is bad then it will throw a code if it reads the wrong temp no code...

Cool thanks a lot.