Engine won't crank, only dead silenc

When the starting key is turned, nothing happens but only a clicking sound. Is a new starter needed?

When the key is turned, the starter is spinning but the engine isn't cranking

The engine starts and idles fine, but lacks power at high speed

The engine starts but dies after a few minutes and won't restart

The engine won't start. It cranks normally, but just won't go

Engine won't crank, only dead silence

Solution:

The starting problem may be due to a dead battery, a loose or corroded battery cable, a bad ignition switch, an open neutral safety switch, or a bad solenoid or starter.

Total silence usually means nothing is getting through to the starter. So start with the battery to check if it has a full charge or if the battery cables get loose, corroded or damaged? Be sure to check both ends of the cables, including the starter and ground connections.

If you don't find any obvious problems with the battery or its connections, voltage may not be passing through the ignition switch circuit to the starter solenoid. A voltmeter or 12 volt test light can help you see if voltage is reaching the solenoid when you turn the key.

If voltage isn't getting through, try jiggling the gear shift lever. Some vehicles may also have a safety switch on the clutch pedal that prevents the engine from starting unless the clutch pedal is depressed. Use your voltmeter or test light to isolate the component that needs to be replaced or adjusted. Sometimes the transmission or clutch linkage may need to be adjusted for the safety switch to work properly.

If voltage is getting through the ignition switch circuit, but the starter isn't doing anything, check the wiring connections on the solenoid and starter. Are they clean and tight? Try bypassing the solenoid. Refer to a shop manual for the proper terminals, then jump the one that routes voltage directly to the starter (usually B+ or BAT). If the starter spins, the problem is a bad solenoid (or poorly grounded solenoid). If nothing happens, the problem is a bad starter that needs to be replaced.

When the starting key is turned, nothing happens but only a clicking sound. Is a new starter needed?

Solution:

The only way to know for sure is to check out the battery, solenoid and starter. If you hear a clicking noise, it means voltage is getting through to the solenoid. But there may not be enough voltage to spin the starter. So start with the battery and cables.

Is the battery at full charge? Are the battery cables clean and tight? Be sure to check both ends. Are the other electrical connections at the solenoid and starter clean and tight? It doesn't take much corrosion to choke off the flow of amps to the starter.

Next, check the wiring connections on the solenoid and starter. Are they clean and tight? Also check the solenoid ground connection or its mounting. Rust or corrosion here can interfere with the flow of amps, too.

Try bypassing the solenoid to see if the starter spins. If it spins, the problem is excessive resistance in the solenoid. Replace the solenoid. If the starter doesn't spin, or turns very slowly, however, the starter is dragging and needs to be replaced.

When the key is turned, the starter is spinning but the engine isn't cranking.

Solution:

Check one of two problems: Either the starter drive on your starter is defective and is not engaging the flywheel to crank the engine, or the flywheel has some broken or damaged teeth that are preventing the starter from engaging.

Starters come in a variety of designs. On some, the solenoid is mounted on top of the starter (direct drive). When the key is turned, the solenoid routes current to the starter motor and at the same time pulls a lever that slides the drive gear mechanism out so it will engage the flywheel and crank the engine. If the solenoid is weak or damaged, it may not be strong enough to overcome the spring tension that retracts the drive gear. So the starter spins but doesn't crank the engine.

On other starters, the solenoid is mounted remotely. When the starter motor starts to spin, it ratchets out so the drive gear will engage the flywheel and crank the engine. If the drive mechanism is damaged or hung up, the motor may spin but not crank the engine.

Regardless of what type of starter you have, it will have to come out for further inspection. The drive gear (which is sometimes referred to as a "Bendix drive") should move out when the starter starts to spin. The drive gear usually has a one-way clutch that is supposed to protect the starter against damage if someone keeps cranking the engine once it starts. The gear should turn one way but not the other. If the gear is locked up or turns freely either way, the drive is bad and needs to be replaced. If the drive can't be replaced separately, you'll have to replace the entire starter.

STARTER TESTING

If the drive seems okay, the starter should be "bench tested" using jumper cables or special equipment designed for this purpose.

CAUTION: Be careful because a starter develops a lot of torque. It should be held down with a strap or clamped in a vice (be careful not to crush or deform the housing!) before voltage is applied.

A simple no-load bench test can be performed with a battery and a pair of jumper cables to see if a starter motor will spin. But this test alone won't tell you if the starter is good or bad because a weak starter that lacks sufficient power to crank an engine at the proper speed (usually a minimum of 250 to 500 rpm) may still spin up to several thousand rpm when voltage is applied with no load.

A better method of determining a starter's condition is to have it tested on equipment that measures the starter's "amp draw." A good starter should normally draw a current of 60 to 150 amps, depending on the size or power rating of the starter. Some "high torque" GM starters may draw up to 250 amps, so refer to the OEM specifications to make sure the amp draw is within the acceptable range.

If the starter does not spin freely, or draws an unusually high or low number of amps, it is defective and replacement is required.

An unusually high current draw and low free turning speed typically indicate a shorted armature, grounded armature or field coils, or excessive friction within the starter itself (dirty, worn or binding bearings or bushings, a bent armature shaft or contact between the armature and field coils). The magnets in permanent magnet starters can sometimes break or separate from the housing and drag against the armature.

A starter that does not turn and draws a high current may have a ground in the terminal or field coils, or a frozen armature.

Failure to spin and zero current draw indicates an open field circuit, open armature coils, defective brushes or a defective solenoid.

Low free turning speed combined with a low current draw indicates high internal resistance (bad connections, bad brushes, open field coils or armature windings).

The engine starts and idles fine, but lacks power at high speed.

Solution:

Check one of two problems: a fuel line restriction or an exhaust restriction.

FUEL RESTRICTION

A plugged fuel filter, crushed fuel line or clogged pickup screen inside the fuel tank can all starve your engine for fuel. Enough fuel may get through for the engine to start and run at low speed, but when more fuel is needed it can't get through resulting in loss of power at high speed. The same kind of problem can also be caused by a weak fuel pump. But fuel pumps usually quit altogether when they fail.

Inspect the fuel line from the tank to the engine. If you don't see any obvious damage, try replacing the fuel filter. If that doesn't help, blowing out the fuel line with compressed air from the engine towards the fuel tank may help dislodge a blockage and debris from the pickup screen. If the pickup screen in the tank is clogged with rust and debris, the tank will have to be removed so the screen can be replaced and the tank cleaned.

Fuel pressure can also be checked by teeing a suitable gauge into the fuel line. If pressure is very low (refer to a manual for the specs), the pump probably will need to be replaced.

EXHAUST RESTRICTION

As for an exhaust restriction, the easiest way to check for this condition is to hook up a vacuum gauge to a vacuum port on the intake manifold or throttle body. If vacuum is low and continues to drop as the engine runs, it's telling you pressure is backing up because of a restriction in the exhaust. The most likely culprit is a clogged catalytic converter.

If the converter has overheated, it may have melted internally. This would restrict the flow of gases through the converter and create a serious backpressure problem that would cause a loss of power at high speed. If the blockage is complete, the engine may start then die and not run at all.

Other causes here may include a crushed exhaust pipe (a visual inspection should find this easy enough), a double-walled pipe that has collapsed internally, or a muffler that has become clogged with rust (rare, because they usually blow out). If you suspect an exhaust restriction, temporarily disconnect the head pipe from the catalytic converter (which is no easy task because the bolts will probably be rusted solid). If the engine now runs normally, you have an exhaust restriction. Inspect the converter and replace it if needed.

NOTE: If the converter is plugged, it failed because something else caused it to overheat. Causes include misfiring spark plugs and leaky exhaust valves. The underlying problem needs to be identified and corrected before the converter is replaced otherwise the new converter will suffer the same fate.

The engine starts but dies after a few minutes and won't restart

Solution:

It may be an exhaust blockage, probably due to a clogged catalytic converter. The converter can overheat and be damaged if excessive amounts of unburned fuel enter the exhaust system. This can happen if the engine has one or more fouled spark plugs or leaky exhaust valves. When this unburned fuel hits the converter, it sends temperatures soaring. The ceramic substrate or pellets that support the catalyst can melt and partially or completely block the flow of exhaust through the converter.

If a complete blockage occurs, the engine will start normally but the exhaust has no place to go. Backpressure quickly builds up and within a couple of minutes the engine quits running. Eventually, the pressure will seep out and allow the engine to restart after it has sit for some time. But the blockage will prevent it from running for long.

The cure here would be to replace the converter. But first, the underlying problem that caused the converter to overheat and fail needs to be diagnosed and corrected -- otherwise the new converter will suffer the same fate.

Other possible causes of this kind of condition include a crushed exhaust pipe, some prankster shoving a potato up your tailpipe, a collapsed inner wall in a double-walled head pipe, or a muffler that's obstructed with rust debris.

The engine won't start. It cranks normally, but just won't go.

Solution:

It may be an ignition, fuel delivery or compression problem.

1. Check for spark first. If there's no spark, you may have a failed ignition module, ignition pickup, ignition coil or open in the ignition circuit (bad ignition switch or neutral safety switch).

2. If you have spark, check for fuel. On carbureted engines, remove the air cleaner, hold the choke open, look down the carburetor throat and work the throttle linkage. If you don't see any fuel squirting into the carburetor, the problem may be a stuck needle inlet valve in the carburetor, a bad fuel pump, a plugged fuel filter, a plugged or frozen fuel line, an obstructed fuel tank pickup screen, or no fuel (or water contaminated fuel) in your tank.

3. If you have spark and fuel, your timing chain or belt may have broken or slipped. If your engine has a distributor, remove the distributor cap and see if the rotor turns when the engine is cranked. No movement would tell you the timing belt or chain (or possibly the cam itself) is broken. Another alternative is to remove the valve cover to see if the valves are opening and closing. This too will show you if the cam drive or cam is broken.

If a cam belt or chain has "slipped a tooth," throwing valve timing off, the valves will still open and close, and the rotor inside the distributor will still turn. But the engine won't develop enough compression to start. A compression check can help you find this kind of problem.