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-   -   New Optispark fails after 50 miles (https://www.corvetteforum.com/forums/c4-tech-performance/4211026-new-optispark-fails-after-50-miles.html)

Warren Seale 11-10-2018 01:24 PM

New Optispark fails after 50 miles
 
I replaced my GM (Delphi) Optispark that failed due to a bad optical sensor module. I lost both the high and low resolution signals. This was 13 years old with 7000 miles on it. I suspect the early failure could have been related to a vent hose assembly that had a clogged filter and a check valve that was no longer checking.

I took a chance with an AIP Electronics Optispark. After installing it, the engine ran fine for 50 miles then developed a miss fire. Cylinder 4 was not getting voltage right at the distributor. I took off the cap and inspected the high voltage components and found that the plastic insulating cover had a damaged area right by the cylinder 4 output. https://beta-static.photobucket.com/...080&fit=bounds=left
The voltage arced through the plastic and into the metal shield.https://beta-static.photobucket.com/...080&fit=bounds=left
I also noticed that the plastic used in the insulating cover appeared to be brittle and had hairline cracks throughout. The voltage arced through one of the cracks. Apparently the crack was compromising the insulating ability of this cover. Some other damage can be seen here.https://beta-static.photobucket.com/...080&fit=bounds=left
https://beta-static.photobucket.com/...080&fit=bounds
=left
https://beta-static.photobucket.com/...080&fit=bounds
=left
So what I did was to take the high voltage parts, cap, rotor, plastic insulator and metal shield from my old GM Optispark and swapped those parts into the AIP Optispark. Hopefully the optical sensor module will last! I also installed a new vent hose filter and check valve.

Some after market manufacturer really needs to step up to the plate and offer a reliable Optispark. All of the new replacements reportedly have quality and reliability issues. If they can accomplish this then they will be the go-to for new Optisparks. Right now you take a chance with a new one so the only other choice is with used or refurbished GM.

LT1inaMGB 11-10-2018 09:13 PM

I got one from this guy https://www.ebay.com/itm/Optispark-I...RQg:rk:17:pf:0 and he guarantees this will be the last Opti you will ever buy. Had it on for a couple years and it has worked flawlessly

dizwiz24 11-10-2018 10:33 PM

And i remember telling them that they were selling a part of questionable quality.

their response was we have a better warranty on it.

my response was, noone wants to be broken down and killed by this part on the side of the road if/when it fails......


their response was you can say that about any part - like tires.

my next response would have been statistics and probability - known issues with non oem optisparks not using mitsubishi optical sensors.

i believe the mods locked the thread.

that was what i had to say about AIP optispark when they were first advertising it here

Kingtal0n 11-10-2018 10:44 PM

it sucks but we've known since the mid 90's that optispark was an accident and was instantly removed and never came back to production.
nothing is going to change, not in 2008 not in 2028, never. 2035 and these threads will still exist if we do. It isn't unexpected and we've all had 20+ years to make amendments and repairati.. reperat... repairation? repairatons... to make necessary changes to avoid the most well known ignition related mid 90's car frequent failure in history (I made that up but its probably true to some extent)
just having some fun :D

drcook 11-11-2018 07:35 AM

The gentleman on eBay that sells the optisparks also buys the old OEM GM ones. They can be refurbed and brought back to life for the most part (2nd gen Opti's). He also has some 1st gen sensors.

cv67 11-11-2018 07:55 AM

If Gm was smart they would start making them again they probably dont need the $. That is what keeps me from buying an LT1 car
Shame is in Ca they can be modded to make a little power and pass smog....dont trust the damn things though.

When I sold my Z I almost did a partial trade for the buyers mint 93..all new MSD opti, nice car. Would run flawlessly til it got warm then the ign would occasionally hiccup here and there outta nowhere then be fine. Not a good feeling sitting in gridlock traffic in 100+ deg heat. If it was legal to convert it to an HEI different story

STEVEN13 11-11-2018 11:06 AM

Thanks for posting this!

Frustrating to hear this as I just purchased one (converting to pin drive). I had the AIP (spline drive) on for about 2 years and it has work fine. However, I installed it with the MSD cap and rotor. At least the optical sensor didn't fail. I may reuse my MSD cap and rotor on this new one.

Steve

Warren Seale 11-11-2018 08:13 PM


Originally Posted by STEVEN13 (Post 1598317188)
Thanks for posting this!

Frustrating to hear this as I just purchased one (converting to pin drive). I had the AIP (spline drive) on for about 2 years and it has work fine. However, I installed it with the MSD cap and rotor. At least the optical sensor didn't fail. I may reuse my MSD cap and rotor on this new one.

Steve

Just be aware that the problem I had was with the plastic shield under the rotor.

STEVEN13 11-11-2018 09:26 PM


Originally Posted by Warren Seale (Post 1598319689)
Just be aware that the problem I had was with the plastic shield under the rotor.

Thank you for the information.

Renfield 11-12-2018 08:09 AM


Originally Posted by LT1inaMGB (Post 1598315274)
I got one from this guy https://www.ebay.com/itm/Optispark-I...RQg:rk:17:pf:0 and he guarantees this will be the last Opti you will ever buy. Had it on for a couple years and it has worked flawlessly

According to your link, what his listing says is: "This distributor is refurbished, tested and guaranteed." What it does NOT say is for how long.

Do you have paperwork stating "Lifetime warranty"? If so, this is far and away the best option anywhere. If not, it's just another pig in a poke.

I have posted this question to the seller as well.

OP, sorry to see your troubles with the AIP. I have installed two of their Optisparks and had none of the cracking you experienced. My high dollar Petris Opti failed in two years. They're all a crapshoot.

Warren Seale 11-12-2018 08:22 AM


Originally Posted by Renfield (Post 1598321081)

OP, sorry to see your troubles with the AIP. I have installed two of their Optisparks and had none of the cracking you experienced. My high dollar Petris Opti failed in two years. They're all a crapshoot.

Just like playing the lottery. It's a pathetic situation.

Renfield 11-12-2018 08:35 AM


Originally Posted by Warren Seale (Post 1598321136)
Just like playing the lottery. It's a pathetic situation.

I try not to drive my '96 farther than AAA will tow. It's a matter of when, not if.

On a positive note, I'm getting good at swapping out the little bastards. :banghead:

dizwiz24 11-12-2018 09:27 AM


Originally Posted by Warren Seale (Post 1598321136)
Just like playing the lottery. It's a pathetic situation.

its not playing the lottery when using OEM parts, particularly the mitsubishi optical sensor.

Why did the OE fail? Well the 92-94 has a design flaw that is easily corrected by adding a vent

the 95/96 dont fail unless someone has done something stupid. Ie. Proactively replaced a working fine oem one with a cheap chinese one and when it fails, they sell the car to you.

or. The vent clogs or gets somehow damaged.

there is a guy on ebay that takes a mitsubishi optical sensor and puts it into an msd optispark.

Again its not lottery. Full confidence in the OEM parts

Renfield 11-12-2018 09:48 AM


Originally Posted by dizwiz24 (Post 1598321438)


its not playing the lottery when using OEM parts, particularly the mitsubishi optical sensor.

Why did the OE fail? Well the 92-94 has a design flaw that is easily corrected by adding a vent

the 95/96 dont fail unless someone has done something stupid. Ie. Proactively replaced a working fine oem one with a cheap chinese one and when it fails, they sell the car to you.

or. The vent clogs or gets somehow damaged.

there is a guy on ebay that takes a mitsubishi optical sensor and puts it into an msd optispark.

Again its not lottery. Full confidence in the OEM parts

You did read the part about this NOT being a sensor fail, right? As far as using OEM parts, MSD as used by the eBay seller is not OEM. ACDelco is.

The factory ACDelco Optispark in my '95 torpedoed at 138K miles. An excellent run for a part that will fail. The bearing failed on my factory OEM ACDelco unit from my '96 at 95K miles. Also, it had a loose screw from the rotor bouncing around inside. I looked high and low for an OEM new unit. They are no longer made.

Do you have some secret line on NIB OEM Optisparks? I can't find one anywhere. Are you able to source reliable replacements for the double-shoulder bearing that GM used in their units? Do you really think the sensor is the only thing that fails in a distributor?

Did you get a lifetime warranty from the eBay seller with the magic bullet non-OEM units?

I love my C4, but it's just not reliable. By design.

Renfield 11-12-2018 10:03 AM

This poor bubba no longer has Optispark issues. :yesnod:


fake 11-13-2018 06:54 AM

Have your old delphi rebuilt by the opti doctor on this site! For 300.00 plus you can not go wrong.

Renfield 11-13-2018 07:35 AM


Originally Posted by LT1inaMGB (Post 1598315274)
I got one from this guy https://www.ebay.com/itm/Optispark-I...RQg:rk:17:pf:0 and he guarantees this will be the last Opti you will ever buy. Had it on for a couple years and it has worked flawlessly

Not exactly.

For those considering the $400+ eBay optispark remans on this link, his only "guarantee" is 60 days. After that he will rebuild it for you. For a price.




drcook 11-13-2018 09:50 AM


This listing is for a service performed on your OEM Opti-spark distributor. I will clean and inspect all components. The bearing will be replaced. Any component found to be inoperative will be replaced or repaired. I will also add a new MSD cap and rotor.
The MSD cap and rotor for the updated, vented design, costs $154.95 from Summit Racing. Right there is halfish of what he is charging for a rebuilt Opti. ($310.00 plus some shipping). Add in the cost of a new bearing (unknown, probably at least $10.00).

Maintenance is the key here. While it is a pain to do, it still needs to be done, just like any other car that is routing high voltage through a distributor.

We all know (well most of us) that an electrical unit that is defective usually goes in the first 60 days if used regularly. At least that has been my experience. Then it settles in and works. We all (well most of us) know that GM (and the other auto companies) really aren't designing cars to last more than 7'ish years. So you have to stay on top the systems, otherwise it is just rolling the dice.


Early Opti-Spark systems on the 1992-’94 Corvette and 1993-’94 used an unvented cap that tended to trap moisture, resulting in internal corrosion, arcing and misfiring. Later Opti-Spark systems used a vented cap with two hose connections (vacuum and air vent) to keep moisture out of the cap.

GM technical service bulletin 87-65-27 offers a fix for Opti-Spark misfiring in the form of a distributor upgrade kit (P/N 10457293 for the earlier applications, and P/N 10457735 for the later ones).
Notice GM tried to deal with Opti issues with their TSB and updated kits.

https://testing-public.carmd.com/Tsb...d/68160/583354


The distributor caps on these engines typically go bad after about 60,000 miles, and the OEM plug wires aren’t the best either. So if you’re doing preventive maintenance on a high-mileage LT1, and the cap and wires have never been replaced, new ones would be highly recommended.
http://www.tomorrowstechnician.com/s...ow-technology/

Other than proactive maintenance, you could either invest in an LTCC unit (I have caught wind of some, NOT MANY, failures) and convert it to coil on plug, or you can get the really expensive coil on plug, new ecm solution that has been talked about here on the forum.

In my research to learn as much as I could about my 1996 and how to modify it and make it live, I ran into mentions that there were other aftermarket solutions that fixed the issues. The folks that made them either found new gigs that paid more, or simply dropped out of the game because not enough people were willing to invest in their products.

In my mind, the marrying of the MSD components with the OEM GM components create a superior product. In fact, I bought one of his to put on the engine when I go through it for the mods I am doing and then I am going to send my still working, 18,000 mile but (in the spring) 23 year old Opti to be rebuilt.

2LZ 11-13-2018 10:38 AM


Originally Posted by drcook (Post 1598327672)
Add in the cost of a new bearing (unknown, probably at least $10.00)..

To me, this is the problem. I don't think anyone's found the double-shouldered bearing. I installed the single-shouldered bearing that was recommended, in both directions, and the shaft still wiggled.
If we could get our hands on the original style bearing, rebuilding these would be a piece-o-cake, as long as the stock sensor was still good and cleanable.

Optidoctor 11-13-2018 12:49 PM


Originally Posted by Renfield (Post 1598326906)
Not exactly.

For those considering the $400+ eBay optispark remans on this link, his only "guarantee" is 60 days. After that he will rebuild it for you. For a price.

Hello from the Optidoctor on ebay,
I offer to rebuild/refurbish any of my optisparks at no cost to the buyer. I do this for two reasons:
1. I believe it is excellent customer service.
2. We can both learn what created the failure and address it.
I offer the free rebuild service for as long as you own your LT-1. As a result, I have learned a lot about these distributors over the past 2 years. For example: A few Optispark II's have come back full of oil. I noted that they were all AC Delco rebuilds and that they leaked air through the bearing area. I evolved my rebuild process to address this issue. Interestingly, the problem was created by Cardone/AC Delco when the base plate is rebuilt.. They inadvertently create an opportunity for a large air leak. Then, the bearing area becomes an easier path for air flow compared to the intake hose and you end up breathing air from the timing chain cover area instead of the clean air from the engine air duct.


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