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Old 03-07-2011, 10:40 AM
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Exclamation Oil Pressure Sender Question

My 3.7L has its oil pressure light flash randomly and very quickly (on/off once or twice then stays off). Oil level is a-ok, no leaks, I'm 99% sure oil pressure is ok and that it's just the sensor or wiring going bad.

Having said that, when I looked at the sensor, I only see 1 wire going into it, a brown wire. the description on alldatadiy.com says it's a "3 wire, solid-state engine oil pressure sensor"...is that right? Why in the word is there only 1 wire on mine? Is there an easy way to replace the wire, or does it roll up in a larger wiring loom that's a PIA to replace?

Thanks in advance for the help!
Alex
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Old 03-07-2011, 02:16 PM
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Re: Oil Pressure Sender Question

Its probably the sender... a quick go - no go, on the sensor is unplug the connector and look for oil inside the connector. IF there is it may not be your only problem (saying that for cya purposes) but it needs to be replaced reguardless.

Another problem is that the sensor uses a pressure differential to deturmine oil pressure (edit... it is not an analog signal, your not going to get a variable signal from this sensor its simply a TURN THE CAR OFF NOW sensor) . It uses atmospheric from the back side of the connector then engine oil pressure on the other side. If the sensor physically fails and allows oil into the connector it can plug up everywhere in the connector it uses to breathe and get atmospheric pressure. SUPER common on the 3.5l v6 and the repair on that consists or removing the plug from the connector and installing a "breather wire" that you simply run up the harness and ziptie up.

It is likely to be your sender, BUT naturally I will not tell you for sure so your motor and give up on you at my suggestion. Replace the sender and clean the connector very well then go from there.
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Old 03-07-2011, 02:28 PM
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Re: Oil Pressure Sender Question

Awesome advice, I'll check the connector and work from there. I'm still puzzled by the 1 and only 1 wire coming out of the wiring loom going into the connector.
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Old 03-07-2011, 03:56 PM
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Re: Oil Pressure Sender Question

dealerconnect shows it being a 1 wire sensor (2 pin connector)... not sure what sensor you were looking at. Its simply continuity to ground much like an engine coolant temperature senosr. When amperage flows the light comes on.
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Old 03-07-2011, 07:07 PM
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Re: Oil Pressure Sender Question

Quote:
Originally Posted by 2005JGC View Post
dealerconnect shows it being a 1 wire sensor (2 pin connector)... not sure what sensor you were looking at. Its simply continuity to ground much like an engine coolant temperature senosr. When amperage flows the light comes on.
didn't know that, thanks again!!
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Old 03-09-2011, 02:41 PM
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Re: Oil Pressure Sender Question

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Originally Posted by 2005JGC View Post
Its probably the sender... a quick go - no go, on the sensor is unplug the connector and look for oil inside the connector. IF there is it may not be your only problem (saying that for cya purposes) but it needs to be replaced reguardless.
It turns out a bit of oil came out of the sender when I unplugged the wiring from it. Do you guys know what could cause that (sorry for being completely misinformed on the topic)?

The sender unit will be replaced asap over the weekend, but I'm curious what other problems I might be having.

Thank you again for all the help!
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Old 03-10-2011, 07:42 AM
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Re: Oil Pressure Sender Question

Its just a failing sending unit, oil is allowed to pass through the sender into the connector. VERY common on chrysler products, thats why I was able to point you at it.
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