What causes a starter to crank slow?

Asked By: Mitxel Widmar | Last Updated: 13th April, 2020
Category: automotive auto parts
4.9/5 (3,079 Views . 37 Votes)
A: Possible causes: a marginal battery, a poor connection in the starting circuit or starter, a charging-system problem, or the battery is being drained while the car's parked. If the slow cranking occurs after driving (engine hot), it's likely a faulty starter or poor charging.

Click to see full answer


In this regard, can a bad starter cause slow cranking?

A starter that's failing may crank the engine too slowly for a quick start, or it may not crank the engine at all. Often, the problem is not the starter but a low battery or a loose or corroded battery cable connection. If the battery's voltage is low and it doesn't take a charge, your customer needs a new battery.

Beside above, what is a slow crank? Slow crank: The starter cranks, but it does not produce enough engine RPMs to successfully start the vehicle. Click, no crank: The solenoid clicks, but the starter fails to crank at all.

Accordingly, what causes a starter to turn slow?

Slow cranking could be the result of several possible conditions, and as you've suggested, the fault might reappear or worsen. Possible causes are a degraded or defective battery, faulty electrical connection, a charging system problem, a bad starter or battery rundown when parked.

What happens when the starter motor starts under load?

During starting of this motor under load, the high initial current, due to low resistance and no back emf, produces a very strong magnetic field and consequently high initial torque. This characteristic allows the series wound motor to be an ideal starter motor.

23 Related Question Answers Found

How do you know a starter is going bad?

What are common bad starter symptoms?
  1. Something sounds off. One of the symptoms of a bad starter is a clicking noise when you turn the key or push the start button.
  2. You've got lights but no action.
  3. Your engine won't crank.
  4. Smoke is coming from your car.
  5. Oil has soaked the starter.

What does a bad starter sound like?

Whirring, grinding, and high-pitched noises are the usual sounds of a bad starter. Since the symptoms of a bad starter can often be mistaken for a battery or alternator problem, make sure that your battery is in tip-top shape before ruling out a starter problem.

Can a bad starter cause voltage drop?

High voltage drop, or unwanted resistance, can creep into a starter circuit in the form of: corroded terminals or connections. loose or poor connections. carbon buildup in relay or solenoid contacts.

How do you bypass a starter solenoid?

How to Bypass the Starter Solenoid
  1. Locate the starter motor under the vehicle.
  2. Locate the two metal contacts on the back of the starter solenoid.
  3. Place the metal blade of an insulated screwdriver across both metal contacts.
  4. Get a friend to help you by turning on the ignition with the key.
  5. Listen to the starter motor.

What causes long crank time?


When an engine cranks for a long time before it starts, either spark or fuel is missing or weak and each has its own reasons. A bad coolant sensor, a bad throttle position sensor (TPS), a bad fuel pump or a plugged fuel filter can all cause a lean condition causing long cranking times.

Why is my car struggling accelerating?

Among the causes of poor acceleration are clogged fuel injectors and/or inadequate fuel pressure/volume. This can cause the vehicle to accelerate slowly, or even sputter and stall, especially at high speeds. A clogged fuel filter can also restrict the amount of fuel that reaches the injectors.

Can spark plugs cause a car not to start?

Yes, it can. If the spark plugs are bad and not firing the spark as they should the fuel/oxygen mix can be very hard to get to ignite. So the answer to your question is yes bad spark plugs can make a car not start. However, that is not the only cause a car might not start.

What are the two types of starter motor?

Starters can be electric, pneumatic, or hydraulic. In the case of very large engines, the starter can even be another internal-combustion engine. Internal combustion engines are feedback systems, which, once started, rely on the inertia from each cycle to initiate the next cycle.

How many amps is a starter solenoid?

The short of it is that it takes 8-10 amps to hold the solenoid in place while starting but the draw can spike to 30 amps while it is engaging.

Can a starter draw too much power?


Yes, the starter can go bad and draw too much power and not turn fast enough.

How do you calculate the power of an engine starter?

Power = torque x angular velocity (P = To), where, co = 2 n ra/60 and n is rpm. Therefore, the output power developed at 1000 rpm with a torque of 8 Nm (at the starter) is about 840 W.

How do you test a starter current draw?

Starter Current Draw Test
  1. Connect the test leads to the positive and negative terminals and then connect the clamp-on amp pickup around one of the battery cables.
  2. Set the voltage meter to Int 18V and adjust the ammeter to read zero.
  3. Disable the fuel or ignition to prevent the engine from starting during the test.

How do you check voltage drop on a starter?

To check the entire circuit, connect the meter positive lead to a clean spot on the starter motor case and the meter negative lead to the negative battery post. Crank the engine and note the reading. The voltage drop on the negative side should be 0.3 volts or less.

How many volts should a starter start?

You can test for proper cranking voltage with a voltmeter while—you guessed it—cranking the engine. The several hundred amperes of current the starter motor draws should pull the battery voltage down to a normal 9 to 10 volts.