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Hyundai Elantra shaking and check engine light flashing

I have a 2006 Hyundai Elantra. I was driving it today, and while idled at a red light, the car began shaking and my check engine light started flashing. I know that means stop immediately, but it was a few minutes before I got to a place I could pull over. By that time, the light had gone from flashing to solid. Since I was only a mile from my house, I drove home. The check engine light is still on and solid, and the car still shakes - more so when I am idling. This all happened after I got my oil changed this morning - I don’t know if that could have something to do with it.

What does it mean that the check engine light went from flashing to solid? I’m worried I could have done damage to my catalytic converter, but I wasn’t driving it for very long while the CEL was flashing, and I pulled over as soon as I could. I want to get it to a mechanic that’s a few miles down the road, but I’m worried I can’t even go that far without causing irreversible damage.

If the CEL light is solid, can I drive it the few miles to the shop? Even though it was flashing earlier and the car still shakes?

The car has 98,000 miles.

Flashing Check Engine light = Pucker Factor Of Ten.

Before I would drive the vehicle, I would start it up, let it idle, and watch if the cat starts turning red.

If it does, shut the engine off, and call a tow truck.

Tester

Check your oil level just to make sure you are good there.

Yes, that’s the first thing I checked when I got home. The oil looked fine.

Okay, I guess I’ll try that. Thank you. Hopefully everything works out

When it flashes, it means there’s a problem that requires immediate attention, an emergency situation as the car may stop working and strand you. When it is solid, it means there’s a problem that must be dealt with soon, but not an immediate emergency. A flashing CEL usually means there’s a misfire condition, and a lot of them, not just an occasional misfire. Misfire means the engine computer has noticed the crankshaft isn’t accelerating as fast as it should be as a result of a cylinder being ignited. And misfires are consistent with the engine shaking, so that’s probably what is going on.

Misfires can be caused by

  • engine overheating
  • contaminated gas or other fuel system problems
  • problem with the air/fuel mixture
  • problem in ignition system
  • engine compression problem
  • inability to move exhaust gasses out the tailpipe (cat or exhaust system clogged)

Perhaps whoever did the oil change knocked a wire or vacuum hose loose.

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