I have no fans on and the engine is hot according to the gauge. If I turn on the A/C the two fans come on just like they are supposed to. The engine came from a 94 Nissan Altima and I used all of the old sensors. I also have my tach not working and several codes for trans.shifting. I looked at the fan relays and switched them around to no avail. I wonder if the computer is screwed up. The car came from a young man who had been driving when it started overheating all of a sudden. We bought the car and took an engine from my sons other car that he wrecked, i do have the computer out of that to try.
For the fans check the ect, engine coolant temperature sensor. located on the thermostat housin, this tells your computer when the temperature is at 228 degrees f which turns on your fan. if the gauge is reading hot it could be either the temperature sensor on the radiator or you have an after market radiator cap(checkers, autozone, pep boys) whatever but the dealer cap will make the temp. read right. the tach is gonna be your crank sensor or cam sensor and your shift codes should be your tranny sensor, not the shift nuetral safety switch.
- If you need clarification, ask it in the comment box above.
- Better answers use proper spelling and grammar.
- Provide details, support with references or personal experience.
Tell us some more! Your answer needs to include more details to help people.You can't post answers that contain an email address.Please enter a valid email address.The email address entered is already associated to an account.Login to postPlease use English characters only.
Tip: The max point reward for answering a question is 15.
If you mean the cooling fan on the radiator, the computer grounds the fan relay when the fan is needed. If the engine temp reaches 220 degrees or you turn on the ac and the fan does not come on, check the relay first.
You have quite a situation. It sounds as though the Coolant Temperature Sensor is faulty. That sensor will control the temp gauge in the dash as well as control the cooling fans when necessary. As to why the fans are constantly running whether the switch is on or not would mean that there is power to the fans bypassing switch, possibly from another connection in the harness. First off I would try replacing the fan relay, it may be stuck closed, just switch it out with another of the same type connection from the fuse box to see if there is any change. If that doesn't work then I would check to see if the wiring from the coolant temp sensor and the fan switch run through the same area of the harness. Its possible that you may have a short circuit at that point. That may possibly explain why the gauge is reading hot when the motor in fact is not. Hope this helps. Good Luck.
You need to diagnose the problem. The fan is doing what it is being told to do by the computer. You stated the temp gage on the dash is in the HOT position. Either the engine is very hot and the fan needs to run to remove heat even after it is shut off or the gage, coolant sensor or temp sender is defective. Try running it temporarly without a thermostat and see what happens, you may have bought a defective thermostat.
appears we have an Air lock scenario and you will need to perform a
the vehicle on level ground, when cold remove coolant filler cap,
start engine and leave to idle, turn heater on full and blower to
max. When engine reaches operating temperature watch and listen near
coolant filler, keep clear as gurgling and hopefully a boil over
should occur. Top up with very warm coolant and wait as it may do it
for heat inside vehicle if warm replace coolant cap but keep an eye
on temperature gauge as the ~Air lock may have moved on from heater
matrix/core so proceedure needs to be carried out again from COLD.
press the Blue button to appraise my FREE Efforts, Thank You!