Opti, Opti No Spark
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Opti, Opti No Spark 
I'll start by saying I bought a new Delphi unit, and will locktite the rotor screws. But....
For all that have been following the exhaust banging pulling timing thread, I had a coolant leak from the over flow tank and so on. Car just quit on me, luckily I just pulled it into the shop and went to work today. I pulled off the opti and fully expected it to be full of coolant. I pulled off the cover and much to my surprise, no coolant completely dry. The rotor screws, o yes, one was on by two threads or so and the other backed completely out. So, so. I cleaned everything with contact cleaner, tested the cap resistance and contact all tested good, I put locktite on the screws and blew everything out. Didn't see any damage to rotor or cap. Is there a way to test the optical sensor, this is just for kicks and grins, I'm not going to put it back in, but I would think there has to be a way to test and see if the optical sensor is working. I did the test before I took it off and you are supposed to have 1-4 VAC at the ICM wire and I had 1.59 VAC, which is on the low scale. BTW this opti came from ebay, all-ignition was the seller. The optical sensor says nothing, no markings on it at all. I bought it before I found all the great information on this site. You guys are darn smart.
Last edited by Rodinator1234; Jan 22, 2012 at 05:21 PM.
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From: Little Rock, AR
You can plug in the opti and spin it with the key ON and you should get spark from the coil and hear the injectors clicking. Not a definitive test, but will tell you if signals are getting out of it to the PCM.
Just put the damn thing on, hook up all the wires,plug in the coolant temp sensor from the water pump and fire it up... If it's ok it will start.. Yes even though there's no water in the engine .. A few seconds wont hurt anything.. And you'll know if the opti is ok or not.. I had one fail because the screws back out ..fixed
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Ok, I was thinking about putting it on and seeing if it would start with out water pump. I didn't know if the screws backing out of the rotor would cause the encoder wheel to flutter and hit the optical sensor, but the more I look at it I'm not sure it could. So you had one back out the screws and then you tightend them down and it was ok?
Ok, I was thinking about putting it on and seeing if it would start with out water pump. I didn't know if the screws backing out of the rotor would cause the encoder wheel to flutter and hit the optical sensor, but the more I look at it I'm not sure it could. So you had one back out the screws and then you tightend them down and it was ok?
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It's dead, no start. I had the old original opti I took off the car when I first got it and tried it and it fired up. I took that opti off because of a massive opti seal oil leak and it looked like crap so I thought I would get a new one. Ebay of course, no deal after all. I did some experiment's with the multi meter and the known broke opti and the known good one. The resistance on the opti plug on the known good one, from a to b is 16.8 m ohms, all other a to b,c,d reads 5.3 m ohms. On the known dead opti, there is no resistance on a to b, and 4.2 m ohms on a to c,d, with b zero. When I get the new Delphi unit I'm going to see what it reads. Might mean something, might not?
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So I checked the new Delphi Opti that I just got. And it also has 16.8 m ohms through the pig tail wiring harness at A and B, and the same 5.3 m ohm on the rest. That means the all-ignition optical sensor is junk. I have the the all-ignition opti, and the 120k wore out ac delco opti that works. I am going to attempt to make one good one out of both of them. Put the good optical sensor and encoder ring in the bad all-ignition opti. You might ask why, that's because the bearing on the Ac delco orginal seems really sloppy. Any one ever remove the optical sensor?
That means the all-ignition optical sensor is junk. I have the the all-ignition opti, and the 120k wore out ac delco opti that works. I am going to attempt to make one good one out of both of them. Put the good optical sensor and encoder ring in the bad all-ignition opti. You might ask why, that's because the bearing on the Ac delco orginal seems really sloppy. Any one ever remove the optical sensor?
Dynaspark fitment & failed AIP sensor:
I think the brass pins measured out at about .125” by .096” for the hole in the sensor.
Since you’re using the AIP housing, the .125” may or may not be correct.
You have to look closely, but the left hole in the sensor is round, the right is oblong.
If the roll pins in the AIP opti are the proper size (maybe about ~.100"?), then you should be good to go without doing something like this.
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Thanks, and yes I have completed the swap yesterday afternoon in fact. I thought it would be a bigger deal than it was. I took the all ignition housing because it had a good bearing in it and felt real smooth from the cam drive, and I put the old factory Delphi optical sensor and wheel in it and used the all ignition cap and rotor. I was able to test it with my multi meter and it tested good for resistance so I sealed it up with silicone and pulled a vac on it made sure it was good, now I think I have a spare. Which with any luck I won't need because I used loctite on the rotor screws of the new Delphi unit in the car and silicone the crap out of the cap and tested for vac through the unit and it's all good. It has a real strong vac signal at the blue elbow now. I don't think the all ignition unit was sealed very well. I'm not singing the opti blues now, it's a tire smoking throw you sideways make the wife mad hot rod now
