Asking for advice on diagnostics on a1994 C4. What should I look into before I replace the Optispark? The car is has "collector plates" and is in very good shape with 66k miles

I don’t have access to any experienced corvette techs locally. I read post #7 in the sticky – Official DIY, Tech Tips from 2009 but have questions. My issue is very similar to what bdw18-123 had. He included a how to link to Corvette Fever about installing a vented optispark, but the link no longer works. http://www.corvettefever.com/howto/16758/index.html Anyone have another how-to link on the vented conversion?

After winter in storage, the car started right up and seemed to run fine until I got a few miles from home… and it just died while driving so coasted to the shoulder. It started up again after a few cranks, but died several times on the way back home. My old Xray scanner gave me codes 16 and 43. Long story short is I installed 2 new knock sensors and replaced a vacuum hose but the problem wasn’t solved.

So I had it towed to an independent shop not far away. They installed a new air filter and scanned it and test drove it. They said 3 of 4 codes were connected to the optical distributor (16, 42, 43 & 36). They cleared the codes and were closing for a two week holiday so I tried to drive it home. It died 4 times within the first 5 miles. After forth time, I called AAA for a tow as the battery was done for the day. Next day I charged the battery and it started right up, and I read the codes as explained in post #18 ***The Ultimate C4 DIY thread.... write ups w/ pics..*** - CorvetteForum - Chevrolet Corvette Forum Discussion . Codes read manually on the speedometer display were: module 1 – H31, H33 H35 & H37; module 4 – H16, H43 & H72

Two days later the battery was dead again so I installed a new battery, and cleared all the codes when it was disconnected. Now only a module 4 code shows up as H43.

I have several YouTube how to's in my book marks. Here is one of the most recent ones I found:
I am hoping to order parts, and hopefully my neighbor and I will get into it sometime soon.

Any advice on the vented install or a Cardone replacement is appreciated.

Cheers

 

Yeah, Corvette Fever went away during the Great Recession.
Here is a link to Petris Enterprises, maybe it will help: Optispark Troubleshooting
Chris was a continuing contributor to Corvette Fever.
Just be patient, you will see some responses from the regulars for he C4 forum.

 

Please DO NOT throw away your original opti. Better yet send it to Brad the optidoctor to be rebuilt. He can change to vented. Don't waste money on Chinese opti. But if you decide to, you want to send to Brad who will buy your old opti for something like $80.00. Dan

 

Still undecided what’s next. I can only find a cardone opti locally fo $400. Petrie is waiting for parts before one is available for my car there. The fellows in the YouTube vid above had to do some modification for the Capone to fit. Am looking to replace the water pump and seals when I am able to get an optispark.
The car startsright away with the new battery, but when I loop around the neighborhood it will shut down once or twice in less than two miles.
I used an AutoXray to cancel the H43 code before I drove it. Now I am only getting code 16. Will read the codes with the manual paper clip method next.
Any more suggestions where to find an optispark?

Thanks for any advice.

 

You really have 3 choices....the rest might have you doing the job twice even if they have a "lifetime warranty"

Opti doctor
Petris
Sac City

 

Is the opti doctor unit the same as the Dynaspark? My search couldn’t find an opti doctor site.

Sac City looks like a good option. Being in Canada we have a small market and fewer vendors by a wide margin. Anyone have experience with Sac City?

Petris is currently out of stock for the unit I need.

Thanks

 

optisparksolutions@gmail.com his name is Brad. Tell him what you need. Dan

 

Agreed Optidoctor would be the choice, you can also reach him through his eBay store: Optispark Solutions | eBay Stores. He goes by the username berrington1.

Make sure to have the optispark harness replaced to a better unit: 94-97 GM LT1 OptiSpark Ignition Extension Harness | UPR (uprproducts.com).

The part was previously recommended by Brad to me, it could prevent you from spending hours diagnosing ignition related stuttering issue just because of a bad connector.

 

this here puts the tit in a wringer.

I agree that sending it to Brad would be the best option, but getting it back and forth across the border could be an issue, as far as cost, shipping delays etc.

Might take a little time to load, is being dragged back from the depths of time

https://web.archive.org/web/20090502...758/index.html

to get to the large image, right click the pics and open link in a new tab

You could email Brad and explain your situation, being in Canada and see if he has any recommendations for you.

 

Thanks for the heads up on that part. Which one did you get 12" or 24"?

 

I got the 12" one

 

I asked the optidoctor about the harness listed above(UPR) and here was his reply:

Yes. I recommend a new harness. There are several manufacturers. I recall there is a company in North or South Carolina that makes a good one.

Basically, manufactured in USA is the key.

I sent this manufacturer (UPR) an email about where its produced, waiting to hear back

another brand I came across is Casper Electronics...Colorado based and their site says designed and manufactured in the USA ($40+ vs $19 for the UPR one)

Thoughts? Does anyone know about the manufacturer out of North or South Carolina?

 

Follow up...I heard back from UPR and the harness above is made in the USA

 

I just received an order from RockAuto for DC Delco parts - water pump, thermostat, plug wires and spark plus. They listed country of origin for customs documents as China for pump and thermostat, Mexico for wires, USA for plugs. Parts were about 1/2 the Canadian price. I didn’t expect this info. No country of manufacture on the part boxes

 

Perfect, domestically manufactured product with good quality and affordable price.

 

Most dead gm optis are just gunked up and wet inside. I'm a big believer in if you have a gm opti, take it apart and REALLY clean it, spray electric cleaner in the sensor. Locktight the rotor screws. Scrape off the carbon from the terminals and rotor blade tip. Reseal with rtv. Its awesome that its serviceable. It gets undeserved flack because owners aren't knowledgeable or lazy. So when in doubt, blame the opti, right?

Anyway Its worth the trouble to clean. Oil/coolant/rain will get in there, vented or not. I think the vented have more oil risk from the vacuum and vent ports. If it doesn't work after a few startups. [Once it took 10+ strong starts], get the Petris unit. But honestly original GM have always been the best. My 93 and 94 both "DIED". I brought them both back from the dead after cleaning. And so have many others. Its not 100% but the odds are really good. Those mistubishi sensors are tough and last. My 94 had over 215k on the original opti when it was wrecked. Ran awesome. My 175k 93 had a cheap opti that got flooded and ruined. I waited and found a used GM opti to clean. Good to go. Then spun a bearing 10k later. I blamed the opti.