leaking knock sensor??

[mikesb]

I have a 1999 camry v6 that has a small coolaant leak under the intake manifold.I thought it might be the bypass hose so i pulled the manifold this morning. The hose was ok but looks like the knock sensor is leaking where the metal shell is crimped over the plastic. Do knock sensors do this when they go bad? Car ran fine and there the service engine light is not on.

[hill8570]

Originally Posted by mikesb

I have a 1999 camry v6 that has a small coolaant leak under the intake manifold.I thought it might be the bypass hose so i pulled the manifold this morning. The hose was ok but looks like the knock sensor is leaking where the metal shell is crimped over the plastic. Do knock sensors do this when they go bad? Car ran fine and there the service engine light is not on.

Unless there is a serious block problem, the knock sensor doesn't contact coolant or oil -- it's just screwed into the metal of the block.

Most likely, the "leak" is coming from somewhere else, and the knock sensor is just getting leaked upon.

[mikesb]

Originally Posted by hill8570

Unless there is a serious block problem, the knock sensor doesn't contact coolant or oil -- it's just screwed into the metal of the block.

Most likely, the "leak" is coming from somewhere else, and the knock sensor is just getting leaked upon.

Thanks for the reply hill8570.
There was coolant residue all along the firewall side of the valley so it must have wicked up the knock sensor.
I have refilled the rear cylinder head with water to the level of intake gasket surface. I'll let it set a awhile and see what happens.

[360glitch]

I cannot speak on this specific knock sensor, however in 1st Gen DSMs (Eclipses, Talons, and Lasers) the knock sensor leaks out a black gooey substance when they go bad. Just thought I'd mention it...

[mikesb]

the material on the knock sensor and along the valley was a purple like color which I asumed was coolant that had started to dry up. The car has Toyota red coolant.
I am now thinking it might be seepage past a head gasket to the outside of the block?
The coolant passages in the cylinders head look new and show no sign of corrosion like you would see in a neglected cooling system.