Oct 24, 2019
16
19
Toronto
VetteCoins
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1995 Corvette, admir
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ON
hey everyone, need your personal and experience on this one. I recently bought a 1995 Admiral Blue C4 Corvette. it has 36,000km, it's in very good condition, sold it b/c he was moving and unfortunately his wife has a bad hip and cant enjoy it like they use too.

I know that LT1's are infamous for their optispark issues. I have not taken it out in the rain or on wet roads b/c I dont want it to break down on me. questions:

- Should I worry about it considering it's a later model LT1?
- Should I by a new optispark and water pump?
- Should I wait until a certain amount of milage to do any changes?

please let me know, I'm 32, my first corvette, I'm somewhat mechanically inclined and eager to listen and learn from your input. thanks again for any replies.
 
I would not worry with that mileage. Drive and enjoy it and do regular maintenance as required. Inspect all rubber parts due to age, belts, hoses etc. I would make sure all fluids have been changed within a reasonable time frame as per manual or 5 years max.
 
I had a 1995 Camaro with an LT1 and an Optispark. In the 18 years (and 90,000+kms) that I owned it there were no issues. Even after my waterpump failed. Just make sure the optispark vent hose never fails. The first year of the optispark had no vent; condensation had no way to get out and corroded the contacts. That was the weakness with the system and why it developed a bad reputation. Hence pay attention to the vent hose.
 
I would not worry with that mileage. Drive and enjoy it and do regular maintenance as required. Inspect all rubber parts due to age, belts, hoses etc. I would make sure all fluids have been changed within a reasonable time frame as per manual or 5 years max.
thanks Turbozig...owner before me did a coolant flush every year and had just finished an oil change. but I will definitely continue the regiment. thank you for your input
 
I had a 1995 Camaro with an LT1 and an Optispark. In the 18 years (and 90,000+kms) that I owned it there were no issues. Even after my waterpump failed. Just make sure the optispark vent hose never fails. The first year of the optispark had no vent; condensation had no way to get out and corroded the contacts. That was the weakness with the system and why it developed a bad reputation. Hence pay attention to the vent hose.
thanks 12cents. good to know, and I'll make sure to check the hoses 👍
 
I have a 95 z28 with the Opti Spark (sounds like the name of a Transformer) and the only issue I have is washing the car at a car wash. If I spray up under the wheel wells I can get the unit wet and then the car won’t start for about 30 minutes. So I don’t spray around the wheel wells.

Just because I can.......
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hey everyone, need your personal and experience on this one. I recently bought a 1995 Admiral Blue C4 Corvette. it has 36,000km, it's in very good condition, sold it b/c he was moving and unfortunately his wife has a bad hip and cant enjoy it like they use too.

I know that LT1's are infamous for their optispark issues. I have not taken it out in the rain or on wet roads b/c I dont want it to break down on me. questions:

- Should I worry about it considering it's a later model LT1?
- Should I by a new optispark and water pump?
- Should I wait until a certain amount of milage to do any changes?

please let me know, I'm 32, my first corvette, I'm somewhat mechanically inclined and eager to listen and learn from your input. thanks again for any replies.
Don't usually use my 93 in the rain but other car was busy. Worked fine in light rain all day. All systems working fine so far.
 
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My '93 ran great until unexpectedly got caught in rain one day. Then the misfiring started...and reoccured whenever it was damp out. The folks at Race Ready replaced the Opti/Water Pump/Spark Plug Wires...and they showed me the guts of the old Opti and two contact points were badly corroded.
 
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My '93 ran great until unexpectedly got caught in rain one day. Then the misfiring started...and reoccured whenever it was damp out. The folks at Race Ready replaced the Opti/Water Pump/Spark Plug Wires...and they showed me the guts of the old Opti and two contact points were badly corroded.
thanks 905cableman, its definitely my worst nightmare to have that issue and it turn out to be a financial burden. definitely saving up though just incase. that way at least I got the parts
 
Nope.

Unless it's an early original example.

Early cars with the optispark had a "non-vented" optispark, newer versions had a vented case which allowed the offending moisture to evaporate before it became a problem.

If I could find it again, I would post up a video of a guy spraying a garden hose (on full blast) directly at the optispark on his C4/LT1 and the engine never misses a beat.

If it really worries you, buy a spare and chuck it in your glovebox. That way, if it does fail, you've got one right there to replace it....
 
Nope.

Unless it's an early original example.

Early cars with the optispark had a "non-vented" optispark, newer versions had a vented case which allowed the offending moisture to evaporate before it became a problem.

If I could find it again, I would post up a video of a guy spraying a garden hose (on full blast) directly at the optispark on his C4/LT1 and the engine never misses a beat.

If it really worries you, buy a spare and chuck it in your glovebox. That way, if it does fail, you've got one right there to replace it....
thanks for the support and info man. just reminds me how awesome this community and forum are 😎👍
 
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Opti problems are way exaggerated. Early Optispark units can be modded to vented like 94 to 96.
Even when a opti fails wrenching is quite straight forward with lots of access.
Pray that you don’t have a heater core failure but don’t worry about the optispark.
 
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my 94 standard coupe has developed a vibration around 3300 rpm on medium to hard acceleration, as you run up through the gears. Vibration noticed 3200-3600 RPM, then smooths out through to red line or lower.
It's not in driveline, as it is independent of driveshaft RPM, and the harmonic balancer is apparently still good.
Some posters have said the Optispark could be the issue. Thoughts?
 
If you recently had your clutch done, it could be the flywheel. I think there was a specific way to put the pressure plate on, or something like that. I would have to research it, but if you put the clutch in wrong it could cause problems. If you haven't touched your clutch disregard.
 
my 94 standard coupe has developed a vibration around 3300 rpm on medium to hard acceleration, as you run up through the gears. Vibration noticed 3200-3600 RPM, then smooths out through to red line or lower.
It's not in driveline, as it is independent of driveshaft RPM, and the harmonic balancer is apparently still good.
Some posters have said the Optispark could be the issue. Thoughts?
My 93 is a automatic but the symptoms you describe are what mine was like, could be described as a stumble under moderate acceleration that smoothed out if I backed off a little. Replacing the opti cured it.
When doing the opti I replaced the water pump, plugs, wires, belt and two seals, the water pump drive seal and camshaft seal.
Good tunes!
 
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