Skip the auto shop - Our mechanics make house calls

Q: Cars cranking but not firing

asked by on

I have replaced just about everything in my car the cam senser the ecu the sparkplug and wires even the coil I put in a new battery and also a new altanater car still wount fire what else should I do
My car has an automatic transmission.

This may be related to many different possibilities, some of which may be related to a lack of spark and some of which may be related to a fuel delivery problem or a combination of both. For example, if the ignition coils, crankshaft position sensor, spark plugs, spark plug wires or ignition module are faulty, this may cause the motor to not produce the spark needed to ignite the fuel in the motor.

In the case of a fuel delivery problem, this may be related to low fuel pressure, faulty or dirty fuel injectors, a faulty or dirty idle air control valve (this relays information about air intake to the computer which makes fuel adjustments), or potentially a faulty fuel pressure regulator or fuel pump. Fuel delivery problems will typically not allow the proper amount of fuel to be delivered to the cylinders which results in a lean fuel condition which can cause backfiring or simply cause the motor not to start as a result of fuel starvation. I would recommend having an expert from YourMechanic come to your location to diagnose your no start problem.

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!
  1. Home
  2. Questions
  3. Cars cranking but not firing

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: Speedometer isn't working

Hi. If your speedometer is not working, and your Check Engine Light this may be a sign that your speedometer sensor has failed. As the speedometer sensor is located in the transmission, underneath the vehicle, I would recommend having the...

Q: Fuel filter change

Hello, while this is a straightforward task, much of this repair requires sensitivity that you are working under the car with a flammable liquid. The essential steps are to: reduce fuel pressure in the fuel system, raise and support the...

Q: How do I use voice command to create a memo?

The voice command system allows you to create memos, so that you can make notes or pen your thoughts while driving. Creating a memo takes a few steps. Press the voice command button, wait until you hear the beep,...

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...
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...
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.