Of the many things that can go wrong with your car, a blown head gasket is one of the worst. It can leave you stranded. The repair is expensive if you have to pay someone to do it for you. It is difficult to do yourself. Diagnosing a blown head gasket can be a tough job, too.
Look for extremely white smoke billowing from the exhaust pipe.
This is a signal that a blown head gasket is allowing coolant into your cylinders. White smoke is almost always a sure sign that the gasket has failed. Check your oil. If coolant is leaking, it frequently ends up in the crank case. The oil will look like light brown sludge. It may be foamy. Your oil level will be high on the dipstick.
Check to see if your car is overheating.
Cars often overheat when the head gasket fails. Coolant may seem to just vanish from the radiator and cooling system. A gasket that does not fail to the outside will not allow coolant to leak onto the ground. The combination of overheating and no coolant puddles point toward a blown head gasket.
Does your car run rough or does it seem to have a real power shortage?
A failed head gasket can often manifest as a power failure in your car. Coolant in the cylinders can stop the spark plugs from firing correctly. This will make the engine miss, sputter, and generally run poorly.
Watch for signs that fluid is leaking from somewhere that does not have a hose or water pump that could be failing.
If your coolant is flowing from the side or back of the engine, suspect a head gasket issue. With antifreeze pouring out of the engine, it is unlikely that any coolant will reach the engine oil. However, the amount of fluid lost can be significant.
Pull your spark plugs and look for traces of antifreeze on the plug and in the cylinder.
Remove the plugs one at a time. Turn the engine over and watch for a spray of coolant shooting from opening. If antifreeze comes out, you need a new head gasket.
Take the car to a mechanic to get pressure checks on the cooling system and the cylinders.
Failures on either side point toward a head gasket problem. Other issues on older and high mileage vehicles can mimic this result. It is critical to pay attention to the other symptoms to verify that it is the head gasket.