Skip the auto shop - Our mechanics make house calls

Q: Doesn't start when it is cold out

asked by on

My truck doesn't want to start when it's cold. I try to start it but it doesn't turn over. It'll start with no problem when it warms up. My car has an automatic transmission.

Hi, thanks for writing in. Electricity is heavily dependent on temperature and other atmospheric factors. Temperature being the most important. Most of the time this sort of problem occurs when the vehicle is hot though. Either way, the diagnosis is the same process. The first thing to do is test the battery as it is the most affected by temperature. The best way to test a battery is with a load tester, (carbon pile or other machine) and a hydrometer which is a measurement of the weight of the battery fluid in comparison to distilled water.

Once the battery has been thoroughly tested, replace it, charge it or continue to the next stage if it is good. A simple test is to tap on the starter while someone is attempting to crank the motor. If the starter takes off, you need a starter. The brushes inside the starter will stick and tapping on it will free them.

With no crank conditions, it is always a bad connection. The question is where is the bad connection. An easy trick to locate it, if electricity is flowing at all, if it is not, this won’t work, is to hold the key in the crank position for at least thirty seconds. Sometimes less, sometimes more. If some electricity is flowing in the circuit, the connection that has high resistance will become hot. Even if this connection appears good, it is not and a thorough cleaning with sand paper is often all that is necessary. Check the battery posts, the connection at the starter and the positive battery cable. These are the most common culprits for this.

If you have come this far, you will now need a wiring diagram and a test light. Maybe a multimeter, but that takes some experience to use effectively. If you haven’t done this sort of diagnosis before, I recommend booking an appointment with one of our technicians for a Car is not starting inspection

Good luck!

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: Loud sound when eccelaratjng.

Hello Hazel, thank you for writing in. When the noise is associated with acceleration, then the issue is likely exhaust, transmission, or engine related. There is also the option that the RPMs are reaching higher levels before the vehicle shifts....

Q: Car cut out and won't start

From what you describe it would appear that your vehicle is experiencing some sort of engine performance issue. If you recently had a new black box installed, and the symptoms only began after its installation, then it may be possible...

Q: Is a flush okay for an older transmission? Or should you stick with a drain and fill.

Most transmission repair shops and mechanics that say they are flushing your transmission are really just transferring your fluid out and new fluid into your transmission. This fluid transfer will take twice the amount of fluid that a normal drain...

Related articles

What Causes Hoses to Leak?
While the largest part of your engine is mechanical, hydraulics plays a significant role. You’ll find fluids at work in a number of different areas. Your car's fluids include: Engine oil Transmission...
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...
What are the Car Pool Rules in Hawaii?
Hawaii is widely regarded as a land of vacation and relaxation, and as such, its scenic roads and routes are far better known than the state’s freeways. But, as with all...