Common Valve Cover Gasket Leaks

If you drive a VW Passat, Golf, Jetta, or GTi, you’ve probably asked one question at some time or another: “Why is my valve cover gasket leaking AGAIN?!?” It’s little consolation, but you’re not the only one, my friend.

Your VW may have the 1.8-liter turbo engine or the 2.0-liter motor. You might even have the 3.0-liter V6. Engine size doesn’t really seem to matter much here. You might start seeing an oil drip from the backside of your engine when you’re underneath changing the oil. You might notice a burnt oil smell or wisps of smoke from the engine compartment. And, on closer inspection, you’ll trace it to the back of your cylinder head right at the top.

Whether it’s never been replaced, it was replaced a few years back, or just a few months ago doesn’t factor in much either. It’s frustrating why it occurs so regularly.

 Valve cover gaskets are contructed of rubber or cork.  They leak because  all rubber gaskets eventually deteriorate, become hard and lose their elasticity over time. Valve cover gaskets are particularly prone to failing due to the constant heating and cooling cycles of your engine that occur between when your VW is running and when it is not.

The valve cover gasket surface may not have been cleaned properly.

When the valve cover gasket on your Volkswagen is replaced, the surface on both the cylinder head and the valve cover need to be immaculate. Totally spotless. Any dirt or oil at all and you could be looking at a completely wasted job that needs to be redone soon after. A professional repair facility that knows Volkswagens (like us at L & M Foreign Cars) is also aware of how particular this step is to preventing a recurring leak.

Replacing the valve cover gasket correctly takes an experienced VW mechanic.
Replacing valve covers can be quite challenging.  It appears to be simple, but in reality this particular repair takes quite a bit of finesse.  Knowing exactly where to put a little extra silicone, or which adhesive to use at which point in the repair takes an experienced Volkswagen technician.  Even once you’ve got it back in place, the bolts need to be tightened in the correct order and pattern using the correct amount of torque, and if the bolts are aluminum they’ll need to be replaced at the same time.

There may be an outside cause of the valve cover gasket leak.

On Volkswagen models, there’s a component called a suction jet pump on the intake manifold. It operates like a PCV (positive crankcase ventilation) valve, relieving pressure in the crankcase so oil seals don’t blow out.

Unfortunately, if this suction jet pump stops working, it accelerates the potential for blowing out seals like the valve cover gasket. The passages in the suction jet pump get blocked by oil sludge and the pressure builds up with nowhere else to go.

A reputable shop (such as ours) knows about this and won’t replace the valve cover gasket without checking the suction jet pump as well.

It might not be the valve cover gasket.

Another possibility, aside from the valve cover gasket, is the cam adjuster seal. It’s on the back of the engine right by the valve cover and looks almost exactly like a valve cover gasket leak.

The cam adjuster seal is a bigger job than the valve cover gasket alone. It requires special tools and some VW-specific knowledge to get it right, and from your history, you don’t want to be tackling this problem again anytime soon.

If your valve cover gasket is leaking, or if it appears your VW valve cover gasket is leaking, why not have VW experts check it out for you? At L & M Foreign Cars, we know your Volkswagen better than anyone. We know what it takes to get it fixed right and at a price you can afford.