The intake gasket provides a seal between the intake manifold and the cylinder head in a car's engine. Gaskets are subject to extremely high temperatures and pressures. A blown intake gasket can cause havoc in an otherwise healthy car engine, but the symptoms can be difficult to detect. Many are ambiguous and can represent different problems. If you suspect that you have a blown gasket, look for some general clues that might prove you right.
Coolant may seep out of the broken gasket and flow across the outside of your engine. You will see orange coolant dripping under the frame of the car onto the road or driveway. A bad leak will cause a big puddle. With a small leak, the coolant may not make it that far, but there still could be a couple spots under the car. There may be a metallic smell as coolant evaporates off of a hot engine block. Dripping coolant may pool under the housing of the thermostat.
Coolant may flow through the gasket to the inside of the engine and mix with the oil. Pull the oil dipstick out and look at it. Oil mixed with coolant will have a thick consistency. Examine the oil filter cap for any rusty-looking residue.
If you are adding coolant to your system, it may be leaking out through the frayed gasket. The need to add coolant often can be a sign of a blown gasket.
Engines overheat when they do not have coolant. If your gasket is blown, the coolant will leak out and the engine will overheat.
Your engine may idle roughly, and you may hear whistling or sucking. This is air being pulled through the leaky gasket by the engine. While the transmission is in "Park," you may feel a slight rocking or tremor as the engine idles. To verify this, get a small propane gas cylinder from a hardware store. Let the engine run and squirt a tiny bit of gas along the edge of the manifold joint. Gas will go through the leak and the engine speed will rise temporally. This indicates that a leak exists and gives you an idea of the location.
