Peugeot Repair Questions? Ask a Mechanic for Answers ASAP
I'd check some basics
1st check for spark by removing one of the spark plugs and plug it back into its lead and rest it on the metal of the engine ( DO NOT hold it on place by hand) then have your assistant turn the engine over whilst you watch the plug. It should give a fat blue spark at regular intervals.
If not then check that there's power to the coil pack (at the other end of the plug lead) using a meter. If there’s 12V at the pack but no spark then check the ECU power supply (fuse and relay) and also the connections to the crankshaft speed sensor.
If there is a spark and its still not starting then its likely that the ECU isn't opening the fuel injectors, if the injectors are working you can hear them click - its difficult to hear them with background noise so use a long screwdriver like a stethoscope, placing the handle end in your ear and the metal tip against the body of the injector whilst your assistant turns the engine over.
If you can't hear anything check the ECU power is present by measuring voltage at the fusebox and on its relay socket if OK then check the connections to the crank speed sensor and consider replacing this sensor if the wiring / connections look OK
If the car will start using a squirt of quick/ easi start into the intake then this confirms the problem is lack of fuel
yes a faulty crank sensor will stop teh engine from working entirely, but as you've already replaced it this is why suggest checking some basics
its possible the wirin to the sensor is faulty rather than the sensor itself - so its well worth checking the wiring and connector for any damage / corrosion
thats the same thing crank sensor = engine rpm sensor
the one on the gearbox is the vehicle speed sensor and won't prevent the engine from starting, check over the engine speed / crank speed wiring as the next step
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