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\Auxiliary water pump

39748 Views 16 Replies 8 Participants Last post by  THE Black Man
Can someone tell me how the Auxiliary water pump helps the cooling system--I use it to fill my system after flushing the coolent or when replacing the cooling system. It's great to do because you don't have to turn the engine on. But I don't know what it's function is besides that.
Just found out that mine isn't working for some reason and thinking this might have soemthing to do with the engine getting warm to a point that would thin out my oil and cause the pressure light to flicker
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all it does is pump coolant to the heater core from the motor. there is 1 pump and 2 valve is for the passenger side the other for the driver side. If you remove it and replace with a "Y" or "T" fitting you will still have heat but will be hot all the time (when engine runs) and you will not have circulating coolant when off. It is true that on a hot day running the heater will help cool the coolant. Engine on or off this will circulate coolant. Check the KTMP on the OBC if it within range it is unlikely that this is your problem. Also, you should not need this to keep coolant at a good can help reduce over heating, to turn on the heat, but that would just be treating a symptom not the problem. With or with out this the car should not leave normal range.
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The aux water pump helps to circulate coolant through the heater core when the car is moving slowly, or stopped. I suppose it can be used to help bleed air from the cooling system.

I believe I've already suggested to you, in another post, to measure the actual oil pressure at the oil filter canister.

You may have a defective switch, too thin oil, or a worn-out engine or oil pump.
an oil pressure gauge should screw right in where the switch is located to measure oil...I believe 50 psi is good and maybe going down as far as 20-30 at idle...and up to maybe 60-70 at high rpms.
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