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E36 //M3 OBD I possible hydro lock. Help!

Discussion in 'E36 M3 (1995-1999)' started by tjrinaldi, Feb 9, 2015.

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    So here's one for you all:

    I have a high mileage track car. I use it 60/40 street/track. Everything great in street driving until cylinders start misfiring. I limp the vehicle back to storage JUST as the engine light comes onand engine stalls. We pull the intake and emissions lines. Very dirty. Throttle body pretty oily (new oil) and there's plenty of new oil puddled into the intake plenum. I will replace ICV and all associated tubing. I will rebuild fuel injectors as some tips broke upon removal. I will clean intake manifold and recondition fuel lines, etc.
    2 plugs were completely munched at the tip; one coil had disintegrated. Oil is leaking through, I believe, the valve cover gasket and into cylinders. This is because loose spark plugs started literally vibrating in their threads. When I removed the plugs there is definitely oil in the cylinders above the pistons. I am scared...
    My questions:
    - is there any reason I should pull the head? ..worried about plug diode pieces in cylinder
    - at the very least, should the valve cover gasket be replaced before firing the engine up with new plugs/coils?
    - if, in fact, I may have hydrolocked the engine what is the procedure to rectify the engine?

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    Ok I would clean the oil out of the spark plug tubes and then remove the spark plugs and see if there is any fluid in the cylinders. If it is full of either oil or coolant then you probably have a issue. To remove the fluid from the cylinder place some towels over the spark plugs holes with weight on it and crank the engine this will remove the fluid from the cylinders. A valve cover gasket will not cause oil to get into the cylinder. Yes it will pool on top of the spark plugs and eat the coil boots away. But the spark plugs seals the cylinder so no oil can get into it. As for the plugs not sure why they would have been damaged once you get the spark plugs out look on the top of the piston to make sure there is no damage. If there is damage depending on how bad you may have to do a rebuild. Also check the threads in the head to make sure they are not damaged. What could have put oil into the engine in a bad crankcase vent system which would in some cases suck oil from the pan and throw it into the cylinders hydro locking the engine. (This is what I think damaged the spark plugs) Inspect all that stuff and let us know we can guide you through what to do and pictures will help.

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