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Discussion Starter · #1 ·
Well the car was running perfectly fine no problems at all for a long time now then last night it rained and dropped down into the 20s and came out to start the car and nothing just cranks and cranks but no fire
I can hear the fuel pump kick in and I hope it's not the optispark considering it was replaced 2 yrs ago
Any suggestions I'm thinking about maybe changing the coil but i don't think that will help at all
 

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You have to start somewhere so do this:
(1). Pull the coil wire off the opti and see if it's sparking. If it's a nice blue spark good that means your opti is receiving spark.
(2). Pull the number one wire from the spark plug (insert an extra spark plug if you have one) into the end of the wire and see if it is sparking.

If you get spark out of coil it means your ICM, coil and opti signals are getting thru. If you're not getting spark from plug wire it likely means your secondary side of opti is toast.

Let us know what you find.
 
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First do a code scan with a obd1 or obd2 scanner, depending on what year car is. Would always be helpful if you post what year car is.

DTC's 16, 41, & 42 are all silent, all disable the ignition and fuel injectors. So if you have these codes your dead in the water.

Report back your findings.
 

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To add to USMCs post, the first thing I would do is pulling a plug wire and getting a spare plug, or pull that plug, and you need to ground the plug to something metal to see a spark, otherwise it had nowhere to go. You can't just hold the plug in front of your face. If do that before the coil wire, basically starting at the end of the spark path and working backwards.

Also, you said rain and cold weather, I know it sucks but moisture causes issues with optis. My dryer exhaust vent used to dump into my garage. If my wife did a few loads of laundry and forgot to open the garage door, everything in my garage got moisture on it. If I then went to start my car, it wouldn't start. I'd have to wait a couple days for it all to dry out. I guarantee this is your problem, you should pull the opti, inspect it, tear it apart, put loctite of everything, dry out the cap, put it back on and before adding coolant or the radiator or fans, try to start it. You may need to hang the waterpump by a bolt and plug in the coolant temp sensor, I can't remember but it takes 2 seconds. Or you can try pushing the car into the sun with the hood open for a couple days and see if it starts after that.
 
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Discussion Starter · #5 ·
I think I'm going to try to dry it out bcuz it is acting like it did when the optispark malfunctioned bfor but I'm not going to mess with it till this weekend when it's warmer and hopefully if water did get in there it will be dried up
 

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Hit it with a shot of starting fluid. If it starts it is a fuel problem if not it is electrical. If it starts and runs after the starting fluid try changing the coolant sensor in the water pump. That adds a little extra fuel on cold start up's.
Skunk
 

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If its only 2 years old I doubt it is the opti. An easy way to check for spark is to pull the coil wire. Use a test light connected to the battery ground and hold the end of the test light about 1/4" from the coil while someone cranks the engine. No shocking yourself this way either. If you have spark it will be obvious. You can also test the ignition coil module connector for voltage and ground - google it for instructions. I just replaced the ICM, which was the cause of no spark on my LT1. It is very simple and only about $80. Hope that's it and not your opti!
 

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I think I'm going to try to dry it out bcuz it is acting like it did when the optispark malfunctioned bfor but I'm not going to mess with it till this weekend when it's warmer and hopefully if water did get in there it will be dried up
Have you had any results with this? I am having the exact same issue except my vehicle still will not start.
 

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Once an opti gets ruin by moisture more often then not they are ruined. However, if you dry it out with either hot air or air or time before you try to start it again it in my theory may work again. I would disconnect the battery and then perform the procedure. I would fan up a hair dryer or heat gun to blow warm air inside with some sort of vacuum on the other end to draw the air thru. Maybe this will work. What opti did you buy?
 

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I just read a similar story with a fellow who had a no-start but did have a spark and in the end it turned out to be his ICM (although there was spark). I'm bringing my ICM to an auto parts store to be checked and picking up a fuel pressure test at the same time. I would suggest that you do the same thing. I've been reading these forums non-stop for 3 days.
 

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First do a code scan with a obd1 or obd2 scanner, depending on what year car is. Would always be helpful if you post what year car is.

DTC's 16, 41, & 42 are all silent, all disable the ignition and fuel injectors. So if you have these codes your dead in the water.

Report back your findings.
Im having same issue my 95 z28 had 41 and 42 codes. So is that the opti that I need to change . cause I have spark. I can smell fuel . even sprayed started fluid won't start. I changed coil, icm. Lots of sensors. Only thing I haven't is the opti. Any info would be great
 

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Code 41 & 42 are for ICM or it's wiring. When you changed ICM, did you put heat sink compound on it's back & on heatsink?

Try downloading the 95 factory service manual at the following link. It will have troubleshooting for codes 41 & 42 in the driveability & emissions section. Also full wiring diagram in section 8.
 
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