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Q: Smoke coming from under my hood.

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I drove home from work today which takes me about 10 mins. I parked my car for about 15 mins then left again. After driving for about 20 mins I parked my car and noticed smoke coming from under the hood. I turned the car off for about 5 mins then started it again and drove to the grocery store. The trip took about 20 mins. Drove home which was about a 15 min drive. Backed in my drive way and noticed the smoking again. I checked my oil, transmission, and coolant levels. All good. Help please.

My car has 186000 miles.
My car has an automatic transmission.

Hello there, thanks for writing in. I would be glad to help you out here. Most likely you have a leak.

When the vehicle engine is stone cold, look around the valve cover gasket for liquid oil and then work your way around and down the engine to see if you can see any signs of "fresh" oil.

Another possibility of this issue could be due to a pinhole leak in a coolant hose that perhaps sprays on a hot manifold.

It is not likely transmission fluid is a cause here, but on a vehicle that age (20 years), you may still have the usual leaks from gaskets, so do monitor the level of transmission fluid.

Due to the different types of odor between leaking (and burning if hitting the manifold) oil and leaking antifreeze, it is likely a mechanic could pin it down for you. Finding coolant leaks in particular is sometimes easy, we just need just to pressurize the cooling system when it is cold and safe to work on.

If it is an oil leak, in extreme cases, oil leaking on a hot manifold can cause an engine compartment fire so if you suspect oil, you do want to have this investigated and resolved. Also, breathing in vaporous oil fumes as you are in or around the car is not particularly healthy. As a car engine ages, the gaskets and seals can often, be the weak point or the area of failure.

Engines have become so reliable, mechanically speaking, but gasket technology has just not kept up. This appears to be the situation you face. Your engine configuration is a fairly simple one , so I’d recommend getting one of our certified automotive technicians to come to your home or office to inspect, diagnose, and repair this issue for you. Hope this helps and good luck!

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