Q: HI! My 2007 PT Cruiser overheated earlier today. The engine was making a knocking sound and shaking. smell of coolant strong.

asked by on July 25, 2017

My car overheated. engine was knocking and shaking violently. fan also quit. smell of coolant, and coolant all over my engine. vehicle tried to die. very hot outside. Why did it overheat?? I had plenty of coolant in there yesterday...

My car has 102600 miles.
My car has an automatic transmission.

Overheating can be caused by a number of things such as low coolant levels, a faulty thermostat, a clogged radiator or a failing coolant fan switch. As you may know the coolant fan switch helps to maintain the proper coolant temperature by turning on and off at specific temperature thresholds. When this switch is not working properly, this can cause the fans to come on intermittently, all the time or sometimes not at all. When this happens you will notice a temperature spike and drop occasionally as the fan comes on and off. When your thermostat is not working properly or is stuck closed, this will not allow the coolant to properly circulate through the engine, which may cause the engine temperature to fluctuate erratically or in some cases just remain hot. You may also have a water pump that is beginning to fail. Water pumps often times will begin to produce a bit of a whining sound when they are starting to fail. A common problem also associated with this is the water pump may begin to leak around the water pump shaft due to the seal being damaged. In addition to leaking around the pump, you may have a leak elsewhere in the cooling system coming from one of the hoses going to or from the radiator. Lastly, you may have a failing cylinder head gasket allowing coolant to leak from the water passages into the cylinders resulting in the coolant being burnt in the combustion chamber with the fuel. If this is the case, you may also notice a bit of white smoke coming from your exhaust which is a product of the coolant being turned into a steam like vapor. I would suggest having an expert from Your Mechanic come to your home to diagnose your cooling system.

Was this answer helpful?
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Fair and transparent pricing

Get a quote

What others are asking

Radiator losing water (no leaking) but overflow keeps gaining water

Based on the information you provided, It sounds like you may have a blown head gasket. What happens is that the high pressure in the combustion chamber squeezes its way through a break in the head gasket into the coolant...

DPF light, traction and engine lights flashing, car has no pulling power, dense blue/black smoke on each start.

Based on the information you provided, it is possible that a failed seal in the turbo is allowing engine oil into the intake. The result would be increases carbon buildup on your DPF (Diesel Particulate Filter). Usually a flashing Check...

2007 Ford Fusion Airbag Code B2290

Anytime the airbag light and system has faults there are specialized equipment and procedures that need to be used in order to properly test the system. If you are getting module faults on this vehicle the most common causes are...

Related articles

The Best Used Cars to Buy If You're Over 50
Shopping Shopping for a car when you’re over the age of 50 begins to shift a bit, as your priorities tend to change. Suddenly it’s not so much about what the vehicle looks like, or how much space it has...
2012 Chrysler 200 vs. 2012 Chevrolet Malibu: Which One Should I Buy?
When you are looking for a small-range sedan, you need to get somewhere quickly and inexpensively, and may even need to take a few kids with you. Slightly larger than a commuter car, these mid-size options offer decent gas mileage,...
A Buyer’s Guide to the 2012 Chrysler 200
In In 2011, Chrysler completely overhauled, updated, and remodeled their entire line, including the introduction of the new Chrysler 200. This reimagining of the old, boring Dodge Sebring sedan was already an exciting move for Chrysler, and the 2012 Chrysler...