Radiator Fans not working correctly / intermittently
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Radiator Fans not working correctly / intermittently
Only thing I think I know is that the relays are good and both fans are receiving power, as they both intermittently turn on at full speed. Car is having overheating issues as a resultant, as previously the temp gauge never went over the quarter mark no matter what. Now, after about 30 minutes of driving, I'm encroaching near the 3/4ths mark.
Neither fan turns on when the AC is activated (thus AC doesn't work and only blows luke warm air).
Both fans turn on full blast after driving for awhile and the engine's been turned off (which should happen). But this only happens some times and not others (erratic).
I've never once have seen either fan operate independently of each other, which shouldn't be the case. When they work, they only operate concurrently.
I did an interesting test. I took off the radiator cap and let the car run stationary for awhile and get up to operating temp. I noticed that the coolant levels would raise to near the top (on the verge of spilling) every 5 minutes or so. Right when this happened, both fans would turn on full speed and the coolant level would drop back down. However, the fans would only stay on for about 5 seconds, then turn off again. My car most likely has a blown headgasket, but that shouldn't have anything to do with the fans.
This cycle would repeat infinitely for as long as I performed this test (nearly an hour). Temp range stayed normal. But I'm guessing this is because the car is at rest and the engine really wasn't being worked.
Also to mention, I was getting a check engine light a month ago, and the obd2 reader stated a coolant sensor temp malfunction. I replaced it with a new unit, and the code went away so I'm suspecting that's no longer the culprit.
Any ideas here?
I'm thinking perhaps the fan switch, but open to any other suggestions. The fact that neither fan engages when the AC is turned on confuses me.
Thanks for the insight!
Neither fan turns on when the AC is activated (thus AC doesn't work and only blows luke warm air).
Both fans turn on full blast after driving for awhile and the engine's been turned off (which should happen). But this only happens some times and not others (erratic).
I've never once have seen either fan operate independently of each other, which shouldn't be the case. When they work, they only operate concurrently.
I did an interesting test. I took off the radiator cap and let the car run stationary for awhile and get up to operating temp. I noticed that the coolant levels would raise to near the top (on the verge of spilling) every 5 minutes or so. Right when this happened, both fans would turn on full speed and the coolant level would drop back down. However, the fans would only stay on for about 5 seconds, then turn off again. My car most likely has a blown headgasket, but that shouldn't have anything to do with the fans.
This cycle would repeat infinitely for as long as I performed this test (nearly an hour). Temp range stayed normal. But I'm guessing this is because the car is at rest and the engine really wasn't being worked.
Also to mention, I was getting a check engine light a month ago, and the obd2 reader stated a coolant sensor temp malfunction. I replaced it with a new unit, and the code went away so I'm suspecting that's no longer the culprit.
Any ideas here?
I'm thinking perhaps the fan switch, but open to any other suggestions. The fact that neither fan engages when the AC is turned on confuses me.
Thanks for the insight!
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