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: Car not staying in gear

Hi. You did not mention if you had an automatic or manual transmission. This can be caused by two different problems. The first cause could be that the transmission mounts allow movement of the transmission and knocks it out of...

Q: My car turns over but it has no spark and won't start

I would recommend starting with checking the ignition coils for spark as well as the spark plug wires. Oftentimes ignition coils are a problem when it comes to producing a spark, especially on a vehicle of this age. Also, try...

Q: Just found out that my vehicle has been leaking oil for at least 2 yrs. Would smelling that burning oil smell cause health issues?

Hi Larry. As the co-founder or a non-profit that focuses on education, awareness and screening for respiratory diseases targeting the automotive community, I am happy to answer a few questions for you to clear up some facts. First, there are...

Related articles

How Do Power Car Windows Increase Passenger Safety?
Power windows are responsible for approximately 2,000 emergency room visits every year. When a power window closes, it exerts enough force to bruise or break bones, crush fingers, or restrict an airway. Though...
Rules of the Road For Iowa Drivers
Driving on the roads requires knowledge of the rules, many of which are based on common sense and courtesy. However, even though you know the rules in...
How to Avoid Back Pain in a Car
If you have back problems, sitting in a car for an extended period of time can be excruciating. Even without back problems, you could experience discomfort and soreness from...