1999 nissan maxima dont start but crake
The first step is to determine if it's a spark, fuel, or compression problem. Here's a quick way to find out which of the three is missing. Remove a plug wire, insert a Phillips screwdriver or spare plug piece of bare wire into the plug wire boot and place the end near the engine block (do not hold the plug wire while cranking the engine unless you want a shocking experience). If there's a spark when the engine is cranked, it has ignition. The problem is either fuel or compression. If the engine has an overhead cam with a timing belt, loosen the cover over the timing belt and check the belt. If the belt is okay, the problem is no fuel. Listen for the electric fuel pump in the fuel tank to make a buzzing noise when the ignition is turned on (you may have to open the gas cap to hear it). You won't hear anything if the pump has died. Diagnostics can now be focused on the fuel pump circuit to determine if the pump, relay or wiring is causing the no start. If the relay has voltage but the pump isn't running, you'll probably have to drop the fuel tank to check the wiring connector at the pump. If the problem is no spark, anything in the ignition circuit that creates the spark may be at fault. Use your AutoTap Express DIY to look for an RPM signal from the Crankshaft Position sensor while cranking the engine. A bad Crankshaft Position sensor is a common cause of no starts. The signal from this sensor goes to the PCM or ignition module that switches the ignition coil(s) on and off. If you have an RPM signal, a bad ignition module or PCM may not be switching the coil(s) on and off. Using a voltmeter, check for voltage at the coils with the key on and while cranking the engine. The voltage should be switching on and off. In ignition systems with a single coil and distributor, a bad coil or a cracked distributor cap or rotor can prevent the spark plugs from firing. On multi-coil, distributorless ignition systems and coil-on-plug systems; one coil failure may cause an engine to misfire, but it won't prevent it from starting. What's causing the no-start? All engines require three things to start and run: spark, fuel and compression. If any one of these isn't there, you aren't going anywhere