Skip the auto shop - Our mechanics make house calls

Q: Car has a little trouble starting but starts. While driving sometimes the lights will dim or my radio will cut off then back on.

asked by on

I have tested the battery and alternator and both test fine.

A: Make sure you have good battery cables and ...

Make sure you have good battery cables and battery terminals as well. Check for any fine cracks on the terminals, which can lead to a loose connection. A faulted sensor like a coolant sensor or air temperature sensor can offer false readings to the ECU and in turn the ECU will send the wrong air-fuel mixture to the engine causing it to start hard or run poorly.

Newer vehicles have a voltage regulator that is integral to the alternator assembly. If the voltage problem is affecting the whole car, this may be the problem. To have all these items checked, I recommend enlisting the help of a qualified mechanic that can inspect the hard start, pinpoint any faults, and perform any repairs that may be needed.

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

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: How do I use a USB memory stick with the radio?

You can connect an iPod, play a CD, listen to MP3s and more with your car’s audio system. It also lets you connect other devices, including USB memory sticks. Doing so is actually pretty simple, too. Here’s how: Turn...

Q: Speedometer broke.

The vehicle speed sensor (VSS) is the most likely cause of your inoperative speedometer. The powertrain control module (PCM) uses the VSS signal to determine the control of outputs such as speedometer operation. The VSS circuit or speedometer gauge could...

Q: no start issue 1990 ford ranger custom v6 2.9l automatic RWD

If, by chance, the fuel has been in the fuel tank "for a while", it won't burn, at least not in an engine. So, the first thing to consider is the age of the gas. The plugs do have to...

Related articles

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 P0052 code means This code is seen when the Engine Control Module (ECM) tries to control 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...
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.