Skip the auto shop - Our mechanics make house calls

Q: My car hums when I try to start it on cold mornings. Battery starter and alternator tested and all are fine. I need help please!

asked by on

I need my car at 7:00 am and it won't start now that it is getting colder. The battery alternator and starter have all been tested and are good my new battery is 100% charged. When I turn the key to start I hear a humming sound for about 3 seconds and then it stops. Sometimes like this morning if I hold the key on start for a while maybe like a full minute it will start. Could it be my ignition switch? I am low on money so I cannot just buy stuff to fix and fix if it still doesn't work. I don't know what to do. Please help.

My car has 154000 miles.
My car has an automatic transmission.

A car battery can appear to be 100% "charged" and still be essentially useless. The only way to determine the viability of a "used" battery is to perform a load test on the battery at a professional battery shop or with a mechanic who has a load tester. If the battery passes the load test (even if it marginally "passes" the test, absolutely get a new battery), the starter relay and/or solenoid are checked for power (i.e., is full battery voltage getting to them and is there close to zero voltage drop). If they are getting power, the starter is probably no good because the bendix drive will typically fail after high miles. A completely useless starter, that is one with a failed bendix drive, will test 100% perfect on a starter tester at any of the big box auto stores, simply because those are freewheeling tests with absolutely zero load on the starter. Once you load the starter, as in try to actually start an engine which presents significant mechanical resistance, the starter simply does not work. My advice is schedule a quick no start diagnostic and YourMechanic will absolutely get you up and running without further 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!
  • Home
  • Questions
  • My car hums when I try to start it on cold mornings. Battery starter and alternator tested and all are fine. I need help please!

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 makes popping noise

Hello. The vehicles cruise control system uses an actuator and cable to open the throttle body and hold cruise. The throttle cable and cruise control cable operate independently, but are both linked to the throttle body. Have an experienced technician...

Q: The factory stereo connector was cut and I need to install a new connector.

Hi there. Look at the wiring on the harness and look at the new connector. Make sure that there are the same amount of wires on the connector and on the harness. Then check the wires. There should be a...

Q: randomly stalls out reqiring a jump start,usally.

You may have a charging system problem if when it stalls you need a jump start. If the battery is very weak you may get random dash lights that appear and other problems. Have the computer's ECM and BCM connectors...

Related articles

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...
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...
How Much Does a Mechanic Make in Vermont?
Automotive technician jobs in Vermont have an average mechanic salary of $37k, with some mechanics earning a salary of $53k.