Skip the auto shop - Our mechanics make house calls

Q: Battery or Alternator

asked by on

The other day I was driving home the car hesitated, would not accelerate and almost all the lights on the dash lit up. I tried to jump start it but it would idle for about three minutes engine would race on it's own and then shut off. I had to have it towed. The negative cable was loose and I replaced it the next day. Jumped the car it did the same thing. Ran for about 10 minutes, raced once and shut off. I did notice some liquid come out of the tailpipe when it shut off. What do you think this is. I had a new block put in last year. I was told it needs oxygen sensors. could this be the problem?

My car has 148000 miles.
My car has an automatic transmission.

This can be caused by a variety of things.

The first couple of things you may need to look into are the possibility of a vacuum leak, or the fuel injection system.

In order for your car’s engine to run correctly, it requires a specific air and fuel mixture to be maintained at all times. If this is ever altered, your vehicle’s engine will react in different ways, much like you describe.

One of the ways this can happen is when too much air is inducted into the motor which happens when there is a vacuum leak. Conversely, this can also happen when too much fuel is inducted into the motor. Either of these two scenarios will cause an imbalance in the air/fuel mixture causing a reaction as you describe.

This can also happen when oxygen sensors are not operating properly. The oxygen sensors measure the air/fuel mixture and relay any corrections to your car’s computer which then makes the corrections. If this sensor is not working properly, it can cause the computer to receive inaccurate information which will then relay an inaccurate change to the fuel system.

This can be a very frustrating problem to detect and often times requires the experience of an expert mechanic. I would recommend having an expert from YourMechanic come to your home to diagnose your vehicle’s hesitation concern.

Was this answer helpful?

Need advice from certified mechanic? Get help now!

Over 1000 mechanics are ready to answer your question.
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

Ask a Mechanic
(100% Free)

Have a car question? Get free advice from our top-rated mechanics.

Ask A Mechanic
Over 10,000 questions answered!

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: 2002 isuzu rodeo blower motor not working. Appears to not have ground. when grounded to chasis I get the motor to run but only in

The ground in your application is probably switched on and off through a controller assembly which also varies the fan speed. Obviously the motor is working when you apply full battery voltage but there is a controller in the circuit...

Q: I have a 2003 Cadillac CTS. My engine hesitates then shuts off

Hi there: Usually when the vehicle has issues cranking over, it's not related to the serpentine belt or an ancillary drive belt. In most cases, this is a battery cranking amp issue or an ignition system issue. On the Cadillac...

Q: Car cannot be started, engine unresponsive

These types of issues can be real tricky. The ignition switch is vital to many of the items in the electrical as many modules and vehicle processes, such as starting, are initiated by the ignition switch. The vehicle starting...

Related articles

How Long Does a Distributor O Ring Last?
The distributor is part of the ignition system in your vehicle and its purpose is to route high voltage from the ignition coil to the spark plug. The spark plug then...
P0052 OBD-II Trouble Code: HO2S Heater Control Circuit High (Bank 2 Sensor 1)
P0052 code definition HO2S Heater Control Circuit High (Bank 2 Sensor 1) What the...
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...