Why no spark from coil
Electrical testing is required. Coil positive wire should have battery voltage with key on. Then, the computer signals the ignition control module to cut primary circuit voltage, after it gets information from the crank position sensor-and other sensors, but primarily the crank sensor. When coil primary voltage is cut, it induces high voltage in the coil's secondary windings. High voltage then travels through the plug wires to the spark plug.
So, no spark could be a bad coil, a bad ignition control module, bad crank or cam position sensor, or even a bad ECU (engine computer). Or it could be a wiring problem. Check for voltage to the coil with key on, as a start.
Probable Causes: Fuel Pump (P0230 to P0233) PCM (P0600 to P0606) Crank Sensor (P0355 to P0399) Fuel Pressure (P0190 to P0194) Chances are the Check Engine Light is not on, but you may find any of the following codes: P0230 to P0233 Fuel Pump codes P0600 to P0606 PCM related codes P0335 to P0339 Crank Sensor codes P0190 to P0194 Fuel Pressure Sensor codes No spark due to a bad crank position sensor, a faulty ignition module or PCM, a problem in the ignition circuit (ignition switch, antitheft system, wiring, etc.), a faulty park/neutral safety switch, a bad ignition coil (only on engines with a single coil ignition), or wet plugs or plug wires (did it rain last night, did you just wash the engine?) A less common cause is a worn starter that draws so many amps while cranking the engine that there's not enough juice left to adequately power the ignition system and fuel injectors. Contributing factors might be a weak battery and/or loose or corroded battery cables. No fuel because of a dead fuel pump, bad fuel pump relay, blown fuel pump fuse, plugged fuel filter or line, or failed PCM injector driver circuit or injector power supply relay. Or, the fuel tank might be empty (don't believe what the gauge is telling you), or the fuel tank might contain contaminated fuel (water or too much alcohol) or the wrong type of fuel (whoops, somebody put in diesel instead of gasoline). No compression because the timing belt or chain is broken, the timing belt or chain is loose and jumped out of time, or the overhead camshaft has snapped.
Thank you so far...fact is that the car had no problem starting before the engine wash although the crank sensor was on the blink, new one was fitted as well as cam sensor and ECU was checked and seems to be ok..i suspect that the person with the hose dislodged a connection or something and the ceu picks up no problems at all...ceu cleared..
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