Starting Problems in Vehiclesby Contributing WriterUpdated June 12, 2017
There are a variety of reasons why a Vehicles will not start properly, ranging from electrical to sensors, starter, battery charge, air intake, fuel delivery and ignition sparks. Knowing how to diagnose some of the common causes leading to starting problems can help resolve them more quickly.
Under The Hood:
- Starting Problems in a 1998 Jeep Cherokee
- Starting Problems in the Ford Super Duty
- Starting Problems With a Volvo 740
- Starting Problems with the Cadillac
Engine Will Not Turn Over
Check the battery connections first. Disconnect the battery cables with a wrench and clean the posts and connectors with a wire brush. Always use a socket or box wrench as an open ended wrench will wear the corners off the bolt on the cable connectors and it will become impossible to fully tighten them.
Switch on the wipers or headlights with the ignition key in the "On" position. If nothing works, the battery is likely discharged and requires charging or replacement.
Switch ignition key to the "On" position and adjust the transmission shifter to ensure it is in the "Park" or "Neutral" position. This only applies to automatic transmissions.
Lift the vehicle up with a jack and rest it on jack stands. Inspect the electrical connection between the battery and starter motor. Replace the main positive cable from the battery if it is damaged and clean and tighten the connection at the starter solenoid. The starter motor is located on the lower side of the bell housing just behind the engine.
Remove the starter motor and electrical connections with a wrench and inspect it to see if the pinion gear has become jammed in the flywheel. In some cases you may be able to unjam the pinion and get it working again but it likely should be replaced before it gets jammed again. Remove the starter and solenoid and have a mechanic test that it is functioning properly.
Engine Turns Over But Will Not Start
Check the fuel tank for fuel. If there is fuel then it may not be reaching the engine. Start by checking the fuel filter. There are over 25 different engines in the Cherokee, but most will either be at the carburetor in older engines, or inline in fuel injected engines. Disconnect the filter with wrenches and inspect for water or dirt. Most filters cannot be cleaned and reinstalled so be prepared to install a new filter. Fuel injected systems must be depressurized before removing the filter.
Test the fuel pump. In most cases this means disconnecting the fuel line at the carburetor or throttle body and cranking the engine while holding a fuel line into a container. The process is more complicated with fuel injected systems but the goal is the same, to see if fuel comes out when the engine turns over. If no fuel comes out then the fuel pump either needs replacing or its electrical connections are loose or corroded or there is damage to the wires.
Inspect the carburetor, if your engine has one. Remove the wing nut on the air filter and lift the air filter assembly from the top of the carburetor. Check if the choke is stuck, the carburetor jets clogged, or the float has stuck. Any of these problems may require analysis and repair by a trained mechanic.
Remove several spark plugs with a wrench and inspect for spacing and buildup of carbon or oil deposits. Inspect the spark plug cables for damage and that they are securely connected at the plug and distributor. Replace any faulty cables. On older models check that the distributor cap is tight and there is not water inside it. Remove the timing chain cover with a wrench and inspect the chain for damage or breakage.
If the Super Duty makes a clicking noise, the battery has likely lost its charge. The battery itself may be dead, but cables or battery components may also be to blame. Look at the positive and negative cables and ensure they are securely attached to the battery. White powder is often a sign of corroded battery terminals.
A Super Duty may not start completely if the electrical wiring is wet. Wiring is also attached to all major components and could pose a problem if damaged, frayed, loose or detached. Damaged or dead relays can disrupt the electrical system. The easiest electrical issue is a fuse box; burnt-out fuses can easily be replaced.
The Super Duty cannot function without fuel. However, this goes beyond an empty tank. Any water in the Ford's system poses a problem, as do fully or partially flooded carburetors. Gas needs to be able to reach the Ford's fuel injectors and pumps. Problems with the fuel system's filter can also immobilize the vehicle.
If the Ford overheats and is hard to start while hot, check and then change the air filter. Also, investigate the starter motor and pinion and service as needed. A malfunctioning alternator may need to be repaired or replaced.
Starting problems with a Volvo 740 can be divided into mechanical, electrical and fuel issues. Mechanical problems may include a grinding starter motor or a broken timing belt. Electrical problems may include a voltage drop coming from an old battery or corroded battery terminals. Fuel injection issues may include a myriad of complicated problems or one as simple as replacing the number one fuse, which protects the fuel pump.
Technical Service Bulletins
Websites, such as TSBData, publish technical service bulletins (TSBs) and recall information for several different production years of the Volvo 740. Some TSBs for the 1989 Volvo 740 include adding a protective tube to the battery cable and cold starting problems. Other TSBs include fuel system, rpm sensor, oxygen sensors, the charging voltage of the battery and the fuel injection control unit. Stay up to date on your TSBs to keep your 740 running smoothly.
Many claims for Volvo 740's include difficulty with cold starts. The 740 is equipped with a cold start sensor placed near the thermostat housing that may need cleaning or replacement. Other cold-start or no-start sensors to check can include the manifold absolute pressure, air intake temperature-control sensor or the coolant temperature sensor.
Security System Threat Message
Cadillac owners can sometimes receive an error message on the car's internal dash messaging system that states "security system threat." The message may then state to remove the key from the ignition and wait three minutes before restarting. However, the car may or may not start after the three-minute waiting period. This problem is often due to a security flaw in the Cadillac that is not allowing the ignition key to be read.
If the car does not start when you turn the ignition key to the "Start" position, this means the starter motor is failing to turn over the engine. The reason for this is often a dead battery. However, it could also be caused by a dead starter motor, a faulty ignition switch or a control wire with a bad connection in the starter motor.
Engine Will Not Start
If the Cadillac's starter cranks but the engine still will not start, there could be a variety of problems causing this -- including a bad fuel delivery system, a problem with the engine electronics (such as the sensors), a faulty distributor cap or internal engine problems.