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Crank, No Start - 1997 Celica ST, 7AFE Engine

510 Views 3 Replies 2 Participants Last post by  sefiro
Hey guys, I've been searching around for a fix but can't seem to find one that works. The car was working perfectly the day prior, then one day it started, and then shortly after, it died. It started up three times and died each time, then wouldn't start again. I'm getting good fuel pressure (roughly 40–50 measured with the fuel pressure tool from Oreilly's). Injectors, fuel rail, fuel filter, and fuel pump are all working. I've already replaced the distributor, rotor, ignition coil, and spark plugs. Spark plugs aren't getting any spark after trying the out of the engine test while cranking. The battery is good. I'm lost on a list to go down for things to check; any help is appreciated.

On another note, I have no idea how to do a simple test on the Igniter. I know it helps with spark for starting the engine, but I don't think it's needed.
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You'll need a meter with a high sample rate. You pin prick the wires and connect the meter. Hz/duty cycle on the meter will give you confirmation of the pulses from the ecu or to the coil.

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You'll need a meter with a high sample rate. You pin prick the wires and connect the meter. Hz/duty cycle on the meter will give you confirmation of the pulses from the ecu or to the coil.

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Hey, I'm gonna be honest, I have a low level in car maintenance and fixing, I have no idea what that is lol
Ok, working backwards

  • High voltage signal is sent to the spark plug which jumps the plug gap to eventually ground to the engine body
  • the signal is allocated to the cylinders by the distributor
-the high voltage signal is created at the coil (acting like a transformer converting from 12v to thousands of volts). The coil uses electromagnetism to create a field around the primary wire to the distributor. When the circuit it's broken, the magnetic field collapses inducing an electrical signal on the primary wire.
  • the circuit feeding the coil is created by the igniter. When it receives a pulse from the ecu, it breaks the circuit to the coil and then recreates it.
  • the ecu sends the pulse based on feedback from the distributor which tells the ecu when it is pointed at the #1 cylinder (on modern cars, this is what the crank/cam sensir does)

The pulses/signals come quickly (1000's per minute) and are so short in length, that the typical display/eyeball can't see them. So rather than display the pulse, the meter calculates how many times it occurrs thus the frequency display.

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