Q: When starting, car has heavy gas smell and starts to smoke from under hood with engine light on.

asked by on October 02, 2017

The car was used to take someone to college -- fully loaded. When going up a hill, the engine light came on and began to flash, but they kept driving it. Afterward, once the car was unloaded and cool, it was started with no problems. Sat for a couple weeks. Then, car was started fine, warmed up, revved, still fine. But as it was driven, within first quarter mile, began to smoke and have heavy gas smell from under the hood. Brought car back home and let sit. Tried again after letting cool. Ran fine for a half hour (highway and local). Ran two more times local with no problem, then happened with engine shaking and some smoke. Very heavy gas smell. Tail has normal water and smells a little like u burned fuel, but grayish in color. I don't have an OBD 2 reader, but codes are set. Thanks for any suggestions.

My car has 185000 miles.
My car has an automatic transmission.

In order to start diagnosis the computer will need to be scanned for codes. The problem sounds like you have a fuel injector leaking or a cylinder misfire. Check engine oil to see if it is overfull indicating fuel has got into the oil of the engine from a fuel injection leaking fuel into the engine. If oil is not overfull then the computer test and codes stored may point to the cause of the problem. Once you get the codes by a mechanic like one from YourMechanic then a diagnosis can be made. I would not recommend driving the vehicle since you may have a fuel leak that may be dangerous to drive it.

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