When your engine is not cranking (turning) over it will be mainly due to three separate areas,
first it could be the battery, cables or poor connection, next is the starter
motor or it's trigger circuit, and finally a problem with the engine. Some of these things are easy to fix while
others can be a little tougher, all in which are described in the guide below. We will go
over each one of these issues in order of popularity and ease. Please visit this
guide if your engine is cranking
over but not starting.
Lets fix it!
The battery supplies voltage to the
starter through two battery
cables, positive and negative, which need to be clean and tight while being free from corrosion.
If you know the battery is good because it's fairly new or you
tested it and it
passed, you could have a
battery connections problem at the terminals or
motor itself, here are the symptoms of a bad connection.
The dash lights are bright you turn the key to engage the starter, then the
dash lights go out and nothing happens.
The starter begins to work but then it suddenly stops, the dash lights go out
and nothing happens.
When you turn the key on and there is no electrical power
Weak or dead battery, If the battery fails a
load test the
battery it will need to be
replaced with a new or good used battery of comparable size and cranking
amps. This can be done easily using everyday tools while wearing protective
gloves to protect against residual acid which can be present on a bad
battery. You can get an
AC Delco replacement battery which last longer at
Amazon, or just head on down
to your local parts store for a replacement.
When you turn the key and the lights stay bright but nothing happens?
The first thing to look for is the security light flashing. An immobilizer
system is built into many vehicles which can disable the starter when this
warning light is blinking. Sometimes the system can become activated due to
a glitch or a procedural error, if this light is flashing the
system needs to be reset.
Vehicles equipped with automatic transmissions are designed with a
neutral safety switch that will not allow the engine to crank over if the
gear selector is not in park or neutral. This is the same for standard
transmission cars but the switch is designed to detect if the clutch pedal
is fully disengaged. This safety feature will not allow the engine to start
while in gear. try moving the gear shift to the neutral position and crank
the car over if it starts the
gear range sensor
(neutral safety switch is bad). On a standard transmission car check to see
if the floor mat has lodged under the pedal not allowing fully travel.
Checking the fuses can be an easy fix, if an electrical surge occurs or
if the fuse ages it can fail causing the starter to not operate. Fuses are located in the
interior fuse panel or power distribution center
under the hood. Fuse inspection
can be done visual or by using a test light, replace any fuse that are found
to be bad.
The starter relay is next, used in the circuit to supply power to the starter solenoid
which engages the starter motor operation. Some vehicles are not designed with
this relay in which case you can skip this step. To be sure if your car is
equipped with one of these relays check your owners manual or the fuse panel
identification information located on the lid of the panel or you can ask
one of our technicians for help.
When this relay fails it can do so in two different ways, first the relay may
make a ticking noise like it's working but the contacts inside the relay are
burnt not allowing the power feed of the relay to be transferred through to the
starter solenoid. Next the electrical coil winding will fail causing an open
circuit not allowing the relay to work (no ticking noise). In either case the
relay must be tested and then replaced if found to be bad.
Before the starter motor will work the solenoid that is responsible for
it's operation must receive a trigger signal. This signal is the final destination
for the voltage which originates from the operation of the ignition switch by
the driver. If everything before this point tests or looks okay you will need to
test the starter motor trigger wire for power while the key is in the crank
position to determine the condition of the starter.
This will require you to get under the car and locate the starter motor which
is usually on the right or left side near the rear of the engine block and in
some cases under the intake manifold like on some Cadillac and Nissan V8 engines. locate the starter solenoid trigger wire which is the
smaller of the two electrical connections. Attach a test light to ground and
have a helper hold the key to the crank position. Hold the point of the test
light on the terminal of the trigger wire on the solenoid, the test light should
light up, also test the large power terminal which is connected to the positive
side of the battery it should also have power. Do not touch the test light probe to ground while checking for power to
avoid a short circuit. If both terminals have power the
starter has failed and
replacement is required. Sometimes you will hear the starter click but not
activate, this is telling you the solenoid is working but the motor part is bad
in either case the starter motor has failed. Many times when electrical items fail it's because there is an open
electrical connection. This means a sharp vibration can sometimes allow the connection to
work again. While tapping the starter housing with a hammer have a helper hold
the ignition key in the crank position or rapidly press the start button. This
can sometimes shock the connection into working again and allow the starter to
turn the engine over. Keep in mind this will only work one or two times, the
starter needs to be replaced
which you can get delivered by
Amazon or the local parts store.
Many abnormal noises can occur while the engine is not cranking over.
These noises include grinding, whirring or a loud clunk indicate and
mechanical failure of some kind.
The starter is a high torque electric motor fitted with a small gear and a
mechanism called a bendix. This small gear engages with the large gear called a
ring gear on the flywheel if the car has a stick shift transmission, and onto a
flex plate with cars fitted with an
automatic transmission. The small gear contacts the large gear only when the
starter is engaged and then retracts after the engine starts and the ignition
switch is let up to the run position. If the solenoid fails it will
not push the bendix gear into the flywheel completely which then creates a
grinding noise. When this small gear wears or the bendix failed is will cause a
grinding or whirring sound which means the bendix isn't working and the
must be replaced.
Once the starter has been removed check the flex plate or flywheel
condition. This means observing the teeth of the ring gear which contacts
the pinion gear of the starter. If teeth or missing or badly worn the
flywheel must be replaced
before installing the new starter. Below is a picture of the flywheel on the
rear of the engine with the transmission removed.
If the starter makes a single clunk noise and then nothing it might be working
fine, the problem could be the engine is not allowing it to work because it
can't be turned over due to a mechanical failure of some kind. To start
troubleshooting remove the serpentine belt and check to see if each of the
accessories such as the water pump,
conditioner compressor and
power steering pump spin freely and are not locked up not allowing the
engine to turn.
With the belt removed check for internal mechanical failures which can stop the
engine from rotating such as a spun rod or crankshaft bearing, broken piston or
rod, dropped intake or exhaust valve or a
gasket. The easiest way to do this is to see if you can manually turn the
engine over by hand. Check for this problem by installing a large wrench or
socket with a long handle fitted onto the front crankshaft bolt and try to move
the engine, it should be difficult but not impossible to turn. If the engine is
locked up it will need to be replaced or repaired.