No Spark in my 3FE 1990 80 Series. At wits end need help please (1 Viewer)

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Aug 24, 2014
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Hey all, really at wits end now. I have replaced dizzy, coil and igniter with new parts, and still have no spark. Have checked relay and all other parts that put spark to the old girl and still nothing. the old girl stopped dead in her tracks about 300 meters from home.
Have been tracing back wiring and connectors thinking it may be something simple and still nothing.

All and any advice will be greatly appreciated.
 

Aggiesdm

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When you put the key in the"on" position, do you have a CEL (check engine light) illuminated on the dash? If not, it could be your EFI relay, fusible links, or your Air Flow Meter (AFM). Have you messed with the AFM recently? Did you remove the 2 screws that hold it to the AFM body? If so, you could have damaged the AFM which can cause your problem. If not, check the fusible link near the + battery lead and also the EFI relay which is in the fuse box under the hood. Make sure you are getting 12v to the large brass screw in the middle of that fuse box. If so, the ECU is getting power and you may have a different kind of problem. If the ECU is getting power, then it's probably one of the 3 things I listed above.

I'm no expert, so please consult others but I think I'm accurate on this point.

If you don't know JonHeld, he's the 3FE guru on this site...look him up. Do a search and read up. There are a number of threads on this subject.
 
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Aug 24, 2014
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Yes have repeated Jon's checklist numerous amounts of time now. have also changed the ECU and it has power. Yes I also have CEL light. have gone over the EFI relay aswell and thats not a problem. have checked the fusible links but they seem ok but will check again today and give them a clean up. reading through some of the threads last night seeming to think it is the AFM, and no havent touched the 2 screws, but have a feeling previous owner may have tampered with it :mad: but have a feeling that it might be the problem. have found one on ebay so just have to wait for it to end atm. Im in Australia so the 3FE engines are very few and far between. I have the correct voltage still going to everything. And really dont want to take her to an auto electrian at the present due to what the buggers will charge me.
 
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If the CE light is illuminated with the key in the ON position, then the EFI circuitry is functioning correctly. The AFM wouldn't prevent spark if the CE light is on, however a faulty AFM can cause the CE light NOT to illuminate and shut down the EFI.
You have replaced everything that would prevent spark so it's time to look at wiring. You need to verify that the ECU is getting the required pulses from the pick up coils in the distributor. You can verify this with a meter at the appropriate pins on the ECU connector.
 
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Yep ECU is getting correct pulses aswell. Have been tracing wires and they are all intact with correct voltage. There is no spark going into the distributor from the coil. Have called Toyota here in Australia and they have informed us they have never heard of the AFM being faulty as others have stated.
 
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Aug 24, 2014
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what would the required pulses be for the ECU just so we can check again Jonheld.
did try a mates ECU and still not running.
 
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Aug 24, 2014
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well have gotten a hold of a new engine loom so will see how that goes. Tried AFM still no go. so trying full wiring loom
 
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The ECU receives the pick up coil pulses on pins 4, 17, 18 of connector E4. If you follow the procedure in my flowchart for checking the coil resistance, you can do this at the ECU to verify. Pin 4 is NE, pin 17 is G-, pin 18 is G1. The ECU then sends out an ignition pulse to the igniter on pins 3 and 22 of E4. The igniter in turn fires the primary of the ignition coil. Since you have replace the igniter, coil, distributor, and ECU we now have to assume all the hardware is working correctly. You are obviously missing something. Are you getting +12 at both the igniter and ignition coil?

Coil_igniter.JPG
 
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Aug 24, 2014
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well i better do an update. we now have spark, we have a broken wire going from the coil to the drivers side fuse box. still yet to find the wire but we have done a temp fix and its on a relay. all that needs doing now is the timing and the old girl should run. its on a seesaw atm it wants to start but just cant. tomorrow is playing around with the dizzy,
 
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I have been following this and glad to hear you have spark and found the problem. Did you check continuity at the fuse panel and each accessory to find the break? I have a similar problem and would like to know how you found the open circuit. That is something free I can check while I wait for parts.
 

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