Bad opti spark distributor
Thread Starter
Heel & Toe
Joined: Mar 2014
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Bad opti spark distributor
Howdy. I have a 94 that the service engine light comes on. It happens intermittingly but my vet still drives and runs good. When I stop and it sits for awhile it may take 3-4 cranks, then starts and runs good. I was told that the opti spark distributor is bad and needs replacing?? When I look at theold paperwork from the previous owner it was changed at 148k. Now has 163K. Is this the characteristic of a bad opti spark?? Thanks, Tom
Last edited by highwaydude50; Apr 22, 2014 at 12:21 PM. Reason: Thanks to the folks here, I resolved the problem
Team Owner
Joined: Feb 2010
Posts: 37,575
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From: Lincoln NE
Welcome Tom!
These fine folks can help you.....http://forums.corvetteforum.com/c4-g...discussion-34/
Good luck!
These fine folks can help you.....http://forums.corvetteforum.com/c4-g...discussion-34/
Good luck!
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St. Jude Donor '16
Welcome, First thing is check it for codes. Most auto parts stores will do for free if you have no way. You can do it with a paper clip. post up in the C4 section, and do a search on opti-spark. also check the tech tips. You came to the right place for advice lots of very knowledgeable members here willing to share.
Good luck
Steve
Good luck
Steve
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Howdy. I have a 94 that the service engine light comes on. It happens intermittingly but my vet still drives and runs good. When I stop and it sits for awhile it may take 3-4 cranks, then starts and runs good. I was told that the opti spark distributor is bad and needs replacing?? When I look at the old paperwork from the previous owner it was changed at 148k. Now has 163K. Is this the characteristic of a bad opti spark?? Thanks, Tom
The check engine light is telling you a "code" has been set.
Find out what code that is before guessing at what might be wrong.
Given the description of "runs good", the Opti seems to be pretty low on the list of possibilities.
Le Mans Master
Joined: Dec 2006
Posts: 5,139
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From: H-Town Texas
Boy, I just can't get over how every time one of these things has the the slightest hiccup, someone points to the opti. Usually the mechanic that knows he's gonna charge $2,000 to replace it. 
I agree completely with the two above. Start with the basics, plugs, wires. Check the fuel pressure regulator as well, these don't last forever. Also, how old is the battery? A weak battery can do this as well. If by 3-4 cranks, you mean rotations, that's not horrendous. It's probably something pretty minor and fairly simple.
I agree completely with the two above. Start with the basics, plugs, wires. Check the fuel pressure regulator as well, these don't last forever. Also, how old is the battery? A weak battery can do this as well. If by 3-4 cranks, you mean rotations, that's not horrendous. It's probably something pretty minor and fairly simple.
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Thread Starter
Heel & Toe
Joined: Mar 2014
Posts: 23
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Thank you. If I'm not mistaken distributors don't take their time going out, they just do. Is this correct? Had two shops tell me the same thing, that the opti spark needs replacing by the code that came up. I wasn't there so not sure. Being I just bought the vette, not sure the last time either it was tuned up or the fuel regulator switch was replaced. I think that is definitely the first steps I will take. Really appreciate this info from you and everyone. will let you know the results. Again, thanks and have a great day. Also the battery is fairly new and the volt gauge reads close to 18.
Safety Car
Joined: Aug 2002
Posts: 3,842
Likes: 230
From: SANTA CRUZ CA
See suggestions:
Thank you. If I'm not mistaken distributors don't take their time going out, they just do. Is this correct?
Not true..... optis destroyed by corrosion may take a year (+-) after moisture intrusion..... some failures can occur immediately
Had two shops tell me the same thing, that the opti spark needs replacing by the code that came up. I wasn't there so not sure.
A code may not always be set, but this link will help..... click on "trouble shooting":
http://petrisenterprises.com/optispark-distributor/
Also the battery is fairly new and the volt gauge reads close to 18.
18V is too high.... should be less than 15 at start-up, then move down to 14+......... may be faulty regulator.
Not true..... optis destroyed by corrosion may take a year (+-) after moisture intrusion..... some failures can occur immediately
Had two shops tell me the same thing, that the opti spark needs replacing by the code that came up. I wasn't there so not sure.
A code may not always be set, but this link will help..... click on "trouble shooting":
http://petrisenterprises.com/optispark-distributor/
Also the battery is fairly new and the volt gauge reads close to 18.
18V is too high.... should be less than 15 at start-up, then move down to 14+......... may be faulty regulator.
Safety Car
Joined: Aug 2002
Posts: 3,842
Likes: 230
From: SANTA CRUZ CA
Thread Starter
Heel & Toe
Joined: Mar 2014
Posts: 23
Likes: 0
Thread Starter
Heel & Toe
Joined: Mar 2014
Posts: 23
Likes: 0
Boy, I just can't get over how every time one of these things has the the slightest hiccup, someone points to the opti. Usually the mechanic that knows he's gonna charge $2,000 to replace it.
I agree completely with the two above. Start with the basics, plugs, wires. Check the fuel pressure regulator as well, these don't last forever. Also, how old is the battery? A weak battery can do this as well. If by 3-4 cranks, you mean rotations, that's not horrendous. It's probably something pretty minor and fairly simple.
I agree completely with the two above. Start with the basics, plugs, wires. Check the fuel pressure regulator as well, these don't last forever. Also, how old is the battery? A weak battery can do this as well. If by 3-4 cranks, you mean rotations, that's not horrendous. It's probably something pretty minor and fairly simple.