Kia and Hyundai's Theta engines have been around for a while, but they're not without problems. Here are some of the most common issues facing these engines.

‘This thing is loose’: Mechanic works on Kia with an engine problem at only 59,000 miles. He realizes it’s a common problem with the gasoline cap ‘That would be $600 pls.’ ...

If you have an older Kia you might be in for a rude awakening. Four out of five mechanics gave the same answer on Kias' most common issue.

So far, Hyundai and Kia have recalled about 2.4 million vehicles to fix problems that can cause fires and engine failures.

The Hyundai and Kia Theta II engine is particularly well-known for engine failures caused by metallic debris interfering with oil flow.