Q: engine fires, but rocks violently and will stall after a few minutes of running

asked by on

I was driving on the highway going about 80 mph (no pedal to the floor) when the engine began decelerating until i could only limp the car about 15 mph. pulled off to the side of the road and fired it back up. engine lit right away, but then would stall within 2 minutes, rocking badly. i had the car checked for engine codes, but nothing came up. It feels like the engine wasn't balancing correctly when it was running. when idling before the incident the rpms weren't always steady, it would fluctuate from a steady 1000rpm to about 700rpm. the sonata had a new timing belt put on less than 30,000 miles ago as well as a new catalytic converter. i replaced one of the coil packs a few months back as well as some of the spark plugs. any idea on how i can figure out what might be the cause?

My car has 138000 miles.
My car has an automatic transmission.

The engine must be checked over by an experienced technician to determine if all cylinders are firing properly and there is adequate fuel pressure in the fuel system. Considering the recent services, the vehicle should be in tip top shape but all previous work must be checked during the diagnostic service to ensure their integrity. I’d suggest hiring one of our mobile experts to save on a tow bill, we can come to you in order to diagnose your stalling issue firsthand. Don’t risk damaging the vehicle under poor running conditions.

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
  1. Home
  2. Questions
  3. engine fires, but rocks violently and will stall after a few minutes of running

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

Q: I have a new fuel pump, new fuel injectors and a new alternator why is my car still not starting up?

Hi There, A number of things may cause the car to jerk such as a vacuum leak, a dirty or faulty mass air flow sensor, or in some cases a bad fuel pump. I would suggest having a professional from...

Q: The car has reduced engine power

Hello there. There are many potential causes for reduced power output. The most likely would be the fuel pump, low fuel pressure, battery, alternator, or fuel filter. A bad throttle sensor can cause this issue but the throttle body itself...

Q: Not running, starting, etc. - 2000 Hyundai Accent

Hello - if you are unable to get anything electrical to work on the car, with or without the key in the ignition (dome light when you open the door?), I would say you need a battery replacement](https://www.yourmechanic.com/services/battery-replacement) performed by...

Related articles

P0240 OBD-II Trouble Code: Turbocharger Boost Sensor B Circuit Range/Performance
P0240 code definition Turbocharger Boost Sensor B Circuit Range/Performance What the P0240 code means P0240 is an OBD-II generic code triggered when the Engine Control Module (ECM) detects the intake boost...
How Much Does a Mechanic Make in Vermont?
Automotive technician jobs in Vermont have an average mechanic salary of $37k, with some mechanics earning a salary of $53k.
P2103 OBD-II Trouble Code: Throttle Actuator Control Motor Circuit High
P2103 means there is a fault with the throttle actuator control motor circuit, likely due to a defective electrical component or part.