Q: My car is still running after turning it off.

asked by on November 26, 2016

I just replaced the battery yesterday. I went to work got there with no problems. I parked it and turned it off. But it sounded like it was still running, I tried to start it again and it wouldn't start. It ran with the car being off for about 10 minutes and then I started to see smoke after about 12 minutes it stopped running but still wouldn't start back up.
My car has an automatic transmission.

Hi there. The noise that you are hearing is commonly known as ’Dieseling’. When this happens, check the ignition switch alignment and see that the switch is turned completely off. If the switch is turned off, then while the engine is still trying to run, disconnect the power to the ignition coil pack and the engine should stop running. If the engine stops running, then there is power feeding from the ignition switch to the ignition coil after the switch is turned off. If this is happening, then the ignition switch needs replaced. If the engine continues to run with no spark, then there is too much carbon deposits in the combustion chamber. I recommend putting sea foam in the fuel tank, the engine oil, and the vacuum system, but one section at a time. This will help clean up the carbon deposits and allow the engine to stop dieseling. Carbon deposits get very hot and stay hot for a long time. When fuel is entered into the chamber, the carbon could ignite the fuel at an earlier time, or even after the injector has stopped running. Oil that has fuel vapors in it will continue to burn when the carbon is hot, keeping the engine running. If you need further assistance with your engine running after turning off the ignition, then seek out a professional, such as one from Your Mechanic, to help you.

The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

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

What others are asking

No low beam lights, 2000 Chevrolet Metro

Hello. There could be a problem with the combination switch not turning on the low beams headlight. The combination switch is what turns on the headlights and turns on the high beams. When this switch fails, headlight operation can be...

service ESC and traction control message and power steering out.

This will require the use of a scanner that can read codes and data form the control module. There may be an electrical issue and not a component issue. A fuse that operates the system could be open and not...

Car alarm goes off for no good reason. At times I have seen the hood ajar error.

Hi, thanks for writing in. Your car is equipped with an anti-theft system which functions based upon the use of sensors that detect the car's points of entry (i.e. doors, trunk, hood, etc). When the anti-theft system is set (usually...

replaced rear engine motor mount and transmission shift is not engaging

Thanks for writing in about your Chevrolet HHR. From what you've described you'll need to check the shift cable to see if the cable is attached to the transmission and bracket. It may have come loose when you lifted the...

I have a 08 Chevy Equinox and 2 weeks ago I was driving and the traction control indicator light came on and suddenly all my clust

This problem is due to electrical connections on one or more computers in the vehicle. Try to disconnect and reconnect all the ECU,s one at a time and inspect the connectors for loose or corroded connections. The connections are known...

My clutch pedal sucked to the floor just had the clutch replaced two months ago 2000 Ford F350 Super Duty

Hello - your symptoms suggest the clutch hydraulics or mechanical linkage components have failed completely. The OEM clutch line includes a "quick-connect" fitting that may have come loose or failed, given the recent maintenance. Checking the fluid level, and that...

Starter problem

This may be a question of a weak battery or potentially a failing starter relay. If there is a fast ticking sound when turning the key, it is likely that your problem may be a battery that is simply too...

Car overheating and heat wont work

The heater not working in some cases may be related to the overheating problem you are also having. This may be due to a faulty heater blower motor or potentially a bad heater core. As you may know, the heater...

Reduced engine power

Hi. The first task is to extract problem codes. Whether the Check Engine light is on or not. The most common source of the "reduced power" for these GM engines is either the wiring connector to the throttle body (connections...

Related articles

The Best Used Cars to Buy If You Get Motion Sickness
For For people that suffer from motion sickness, even on the shortest car trip, riding in a vehicle can prove to be unbearable. What’s great is that there are a number of cars on the market that can help to...
The Best Used Cars to Buy If You Have Limited Mobility
When When you have limited mobility there are a number of challenges you face, one of these can be with your vehicle. Finding a car that meets your specific needs, and addressing your challenges can mean the difference between being...
The Best Used Cars to Buy If You Get Motion Sickness
For For people that suffer from motion sickness, even on the shortest car trip, riding in a vehicle can prove to be unbearable. What’s great is that there are a number of cars on the market that can help to...