Car starting problems can be worrisome particularly when your car starter remains engaged with the engine after starting and produces that abnormal noise.
Do you want to know the reasons why your car starter can fail to disengage and possible fixes?
In this post, I cover the common causes of why a car stater can fail to disengage, how you can recognize that the starter is still engaged, the dangers this poses, and possible fixes.
What Happens when a Car Starter Stays Engaged?
This happens when the ignition key has been turned to the START position and the car starter has successfully started the car engine.
The starter then continues to mesh and rotate with the car engine instead of immediately disengaging with it.
The disengagement is necessary to avoid the scenario where the engine rotates the starter at high speeds that can damage and shorten its service life.
In addition to continuing to rotate at high speeds, the starter makes an unusual sound.
Note: The starter engagement may only last a few seconds or longer than that.
You may also want to read: Can a car starter drain the battery?
Why a Car Starter sometimes Stays Engaged | 7 Causes
Some of the common reasons why a car starter can stay engaged with the engine are:
#1. Bad or damaged starter
You can also have a case of damaged magnetic switch contacts on the car starter that are stuck in the closed position that keeps the starter engaged with the car engine.
#2. Problem with the car starter control circuit
It could also be a case of a problem in the starter control circuit, for example, damaged cable connections or weak cable contacts that cause voltage drops in the circuit.
The voltage drops then reduce the availability at the starter that is necessary for the starter’s magnetic switch to work properly.
You may also want to read: Why your car battery voltage drops overnight?
#3. Faulty brand new starter
It can also be a case of a faulty yet brand new starter with a malfunctioning solenoid.
#4. Bad or damaged ignition switch
If your car’s ignition switch contacts are bad or damaged, for example when they are stuck in the closed position, the starter can fail to disengage.
#5. Damaged neutral or park start switches or clutch start switch
Bad connections in the neutral or park start switches for automatic vehicles and the clutch start switch for manual transmissions can also cause voltage drops that affect the magnetic switch’s ability to work properly.
#6. Bad wiring
If you have just installed a new replacement starter, check that you have made the correct wire connections to the starter. Interchanged wire connections can also cause the problem of the starter motor failing to disengage.
#7. Keeping the car ignition in the START position
Lastly, if you keep the car’s ignition key is in the START position, this also engages the starter for as long as the ignition is in the START position.
Symptoms a Car Starter is Still Engaged
You can tell that the car starter has failed to disengage with the car engine when:
- The starter motor continues to spin after the car engine has started – it should stop!
- There is an abnormal noise from under the car hood after the car engine has started likely caused when the starter motor remains engaged with the running engine.
The Dangers of Car Starter Staying Engaged
Failure of the car starter failing to disengage with the car engine is bad for the starter in the following ways:
It reduces service life of the starter resulting from the damage caused to the starter when it is pushed to rotate at high speeds by remaining engaged to the car engine after it has started.
How to Prevent a Car Starter from Staying Engaged
The tips below can help minimize the chances of a stuck car starter:
#1. Double-check and confirm that the right cable connections are made ( follow the manufacturer guidelines) when installing and connecting a new starter helps minimize the likelihood of a car starter remaining engaged with the car engine.
#2. Check that the wiring connections for the starting circuit are clean, firm, and solid particularly after making component replacements to the circuit – ignition switch, starter.
Bad connections can cause voltage drops that can affect the car starter from properly engaging and disengaging from the engine.
How you Can Fix a Car Starter that Stays Engaged?
- Check that there are no excessive voltage drops in both the starter supply and magnetic switch when starting the car.
These can cause the car starter to fail to disengage the engine.
Follow the vehicle service manual when conducting these voltage drop tests and confirm what the acceptable voltage drop levels are.
If there any excessive voltage drops, investigate them or consult a qualified auto technician.
These may be bad connections or damaged cabling.
Repair or replace any such bad connections.
- You should also check the ignition switch contacts and connections.
Confirm that they are firm and make solid connections and that the contacts make and break the starting circuit properly when you switch the ignition to START and release it.
If there are any bad – shorting or stuck contacts with the ignition switch, magnetic switch, or starter relay, replace the respective faulty component.
How to Fix a Stuck Car Starter?
If your car starter appears stuck with the starter motor continously running even after the ignition key has been removed, then it is likely a case of a damaged solenoid.
The solenoid contacts may be welded together.
Some users have managed to loosen the stuck car starter solenoid by tapping the housing with a hammer.
This can fix the stuck solenoid in the short-term but replacing the solenoid is probably a more reliable and long-lasting solution.
In many car starter systems, the starter should immediately disengage as soon as the car engine has started.
Failure to disengage can shorten the service life of the car starter.
Delayed or failed disengagement of the starter may be a result of voltage drops in the starter circuit, a faulty starter or ignition switch.
Even keeping the starter in the START position for a long time can keep the starter engaged.
One way to minimize this problem is to check, confirm and follow the wiring connections particularly when installing new starting system components.
Check also that there are no voltage drops in your starting circuit wiring.