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Discussion Starter #1
I have a 95 ss and after replacing the opti i can not get it to start. The engine cranks but has no fuel or spark. I did take the crankshaft hub off to replace the seals on the timing cover could it be I did not align it properly when re installing?also i cannot hear the fuel pump kick on. All the fuses are good and relay. Help!! Thanks!!
 

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No fuel and spark suggests that the computer is not seeing to position signal from the Opti. Double check the 4pin harness connection on the pass side. If possible get a scanner on it and see if it is reporting an RPM signal.

If this is a cheap Autozone or Orielly's type replacement, I suspect out of box failure of the non-mitsubishi brand optical sensor.

-Brian
 

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Discussion Starter #4
The timing cover was leaking oil everywhere figured while i had it apart I’d replace the opti.
 

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IMPORTANT! Do you have ability to immediately retrieve your original opti? If so, do it. Immediately. There is high probability your original is better quality than many of the aftermarkets out there. The optical sensor is gold.

In addition to high defect rate of aftermarket optical sensor, the track record shows persistent issues with numerous aftermarket suppliers with poor quality parts and poor quality assembly.

To answer your question, yes numerous fellows replacing their opti reported finding out they first installed the cog into the wrong pocket.
 

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And once you have your old opti back in hand, use it to test:
  1. Disconnect your fuel pump harness at the back of the car (driver's side behind bumper).
  2. Disconnect 4-pin wiring harness from passenger side of new optispark.
  3. Connect 4-pin harness to your old optispark.
  4. Turn the ignition on but don't start the car.
  5. Spin the old optispark by hand. If you hear the injectors clicking, you know that the 4-pin harness circuitry is good.
FWIW I always start the car as soon as I have the new optispark hooked up, without the water pump or crank damper on, just run it for 10 seconds, to make sure everything is working. Then I install the rest of everything.

Also, if you took your crank hub off, did you notice the groove in the hub from the seal? Rock Auto and others sell a sleeve that easily presses onto the hub (with the appropriate and inexpensive tool) and gives you a brand new surface for the new seal to ride on.
 

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No reason to replace that opti. Clean it, put it back on.
 

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Yes, if possible, get your old opti back.



QUOTE: "To answer your question, yes numerous fellows replacing their opti reported finding out they first installed the cog into the wrong pocket."

The opti will not mate up to the timing cover if installed improperly. Meaning it is not tight to the TC. Simple examination shows the difference in the pockets.
 
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I have personally missed the cam dowel to opti rotor alignment before. Short dowel, aftermarket opti deeper pocket who knows why. It happens but, I still had spark and fuel, just at the wrong time in the firing cycle.

-Brian
 

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Discussion Starter #10
I have personally missed the cam dowel to opti rotor alignment before. Short dowel, aftermarket opti deeper pocket who knows why. It happens but, I still had spark and fuel, just at the wrong time in the firing cycle.

-Brian
I took the new one off it was aligned properly and put the old one back on. I heard the fuel pump turn on when i turned the key but still no start.
 

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"and put the old one back on". Well then all is not lost. One step getting closer to square one.
"I heard the fuel pump turn on when i turned the key but still no start." But did you shoot ether in while cranking? If it was running well before any work, the first guesses go to upset opti harness (Shockr's notes), connection with coil, even fuel pressure regulator?
 

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Yes, I also have put the opti on with the pin in the wrong place , and it ran.
Then i realized the that hole in the side of the opti shaft ligned up with the cam pin. So now i always turn the engine so the cam pin is at 12:00 and then have the hole in the opti shaft at 12:00. You can watch that holes position from above while sliding it in and get it positioned right easily.
 

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Tests from every OPTI no start thread.

No tool tests:
listen for the fuel injectors.
Smell for raw gas at the tailpipe.
Check the OPTI to sparkplug fireing order.

Easy tests:
Use a sparkplug to show spark is getting to the end of a sparkplug wire.
Or connect sparkplug at the coil wire to see if there is spark from the coil.

Easy tests with special tools:
Put a noid light on a injector wire.
Put a fuel pressure gauge on the fuel rail.

Checks with a live data scan tool:
Do you have a OPTI code?
Do you have live data RPM when cranking?

Tests with a multimeter from:
OPTI and Spark Test

Test with a spare OPTI:
And once you have your old opti back in hand, use it to test:
  1. Disconnect your fuel pump harness at the back of the car (driver's side behind bumper).
  2. Disconnect 4-pin wiring harness from passenger side of new optispark.
  3. Connect 4-pin harness to your old optispark.
  4. Turn the ignition on but don't start the car.
  5. Spin the old optispark by hand. If you hear the injectors clicking, you know that the 4-pin harness circuitry is good.
sherlock9c1
 
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