Oil leak at CMP sensor pins??

lmorris · July 13, 2012

Anyone seen a CMP sensor leak through the pins and into the harness. Changed one 3 weeks ago because that was the only rational source for the leak and it's back with a wet harness again. It is possible I didn't clean the harness as good as I thought, but I just thought I would throw this out there to see if any others have run into this.

Alex Bruene · July 14, 2012

I've only ever seen leaks from the outer o-ring.

Keith Browning · July 14, 2012

Meant to add my thoughts to this the other day... In looking at the construction of this sensor and the fact that it is not exposed to pressurized oil I want to say that it is highly unlikely that this sensor would or could leak from the terminals without serious damage to it. Much less a second sensor.

Like Alex I have only seen the outer o-rings leak but I will add that I have never seen that cause oil to even touch the connector or harness.

Was UV dye used to trace the leak?

Matt Saunoras · July 15, 2012

I thought the exact same thing about my 6.0. The first time I changed the cam sensor the original sensor and connector were soaked internally. I couldn't imagine how the hell oil would wick into the connector so I just figured the sensor was leaking through the pins, but really that doesn't make sense.

Either way I put a new sensor in it and it still leaks, it's probably rust buildup in the hole causing it not to seal.

lmorris · July 16, 2012

No UV dye was not used. When it came in the first time I could see no leak. The block was dry. Just by chance I focused on the harness and saw it was slightly wet, so I unplugged the CMP and oil started dripping out of the connector. I traced the harness all the way up to the top of the engine and found no other sources of oil entering the harness.

The second time it came back with the same thing. This time I also found the upper rad hose was starting to leak. I can't see that having anything to do with the oil leak. Unless there is something in the harness that can look like oil if hot enough and washed with coolant.

Anyways, the customer is going to keep an eye on it for us.