Cranks Excessively Before Starting
Car Starting Issues
Helpful Information
The definition of extended engine crank time is, when the ignition key is turned to the crank position, the engine takes longer than usual before it will start running. (Extended crank time.) When an engine is cranked over it should fire up in about a three second time period. If a starter is weak it can cause the engine to crank slower than usual, which causes the engine to build compression slowly. This can be caused by a weak battery or starter motor with no malfunction of the engine.
Best Practices
- Regular engine tunes up's and fuel filter replacement can stem hard starting conditions.
- To prevent engine cylinder low compression change motor oil and filter at recommended intervals.
Step by step instructions on how to repair an automotive engine that cranks excessively before starting. This article pertains to all cars.
Difficulty Scale: 4 of 10
Tools and Supplies Needed
Before repairs begin, park the car on level ground ,in park with the emergency brake set.
Automotive Engine
Step 1 - For an automotive engine to start and run correctly the engine tune up must be kept up to date.
New Spark Plug
Step 2 - For an engine to start up when cranked over the fuel system must be quickly pressurized. Not only does the fuel pump need sufficient pressure at start up, it needs to be able to hold pressure for a short amount of time while the engine is off. Perform a fuel pressure and regulator test using a fuel pressure gauge. Its also a good idea to remove the fuel filter to check for blockage.
Fuel Pressure Test Gauge
Step 3 - An engine depends on vacuum to allow the engine to start up and run properly, if there are leaks in the vacuum lines the engine will have an extended crank time before starting. Inspect the engine's vacuum lines and repair broken or dilapidated lines.
Vacuum Line
Step 4 - At the air intake port of the engine known as the throttle control motor or throttle bore, mass volumes of air leave deposits called choking. These impurities pass through engine despite the air filter and build up over time. Servicing this unit as part of a regular tune up is necessary for proper operation.
Throttle Actuator Cut-Away
- Flashlight
- Fuel pressure gauge
- Wrench set
- Screwdriver set
- Protective eyewear and gloves
Before repairs begin, park the car on level ground ,in park with the emergency brake set.
Automotive Engine
New Spark Plug
Fuel Pressure Test Gauge
Vacuum Line
Throttle Actuator Cut-Away
Step 5 - The idle air control motor adjusts the amount of air via the computer released into the engine at idle. This device is subject to choking much like the throttle bore. To check this condition remove the IAC motor and inspect, if the plunger of the motor has deposits, clean with carburetor spray or replace the motor with a new unit. Also, clean the air passage ways with cleaner before re-installing the idle air control motor.
Idle Air Control
Step 6 - The air intake boot connects air to the throttle body of the engine and if torn or broken it creates a lean fuel/air mixture causing excessive cranking. Inspect theair intake boot from the throttle body to the mass air flow meter.
Reinstalling Inspected Air Intake Boot
Step 7 - A fuel pressure regulator regulates fuel pressure to the engine injection system. If a fuel pressure regulator diagram ruptures it can allow raw fuel into the engine through the vacuum feed line attached to the intake manifold. To check the fuel pressure regulator for this condition remove the vacuum line from the regulator and check for the presence of fuel inside the vacuum line, if fuel is present, replacement is needed.
Fuel Pressure Regulator Check
Step 8 - Engine cylinder compression is needed for an engine to run properly. Once an engine has reached its life expectancy the compression drops due to piston ring and cylinder bore wear causing a longer than normal crank time.Perform a compression test to check for this condition.
Piston Rings
Idle Air Control
Reinstalling Inspected Air Intake Boot
Fuel Pressure Regulator Check
Piston Rings
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