pcolt94

Replaced opti back in 06 (about 70K miles ago) and have same classic symptoms. If I could buy another GM original unit like back then, I would probably buy one. So it looks I will buy a Deltec or replace the cap. If I had a GM unit I would not hesitate to replace the opti with all the work that has to be done.

So here lies my first question. I do not know if the Delphi opti has a Mitsubishi optical unit. To me that is an important factor and is why I do not want to change the body. What kind of optical unit does it have and is it reliable?

Question 2, my feeling is that the cap is probably the problem. I could save myself few hundred dollars and just change the cap. Is that a good idea?

Car has no starting problems, dying problems and no codes . Runs well except for the opti symptoms in high gear when accelerating when hot.

JMelton

Maybe it's time to do the Coil Pack conversion.

C409

..... Symptoms are just that ... symptoms ... have you ruled out some of the other possibilities ? ... when were the spark plugs changed ? how about the wires ? fuel filter ? ... have you Ohm'ed the injectors ? .... If you have a factory service manual , please consult the diagnostic flow charts within for helpful information ...........

Daredevil95

Your lucky getting 70K out of your opti! I would install a AC Delco or MSD or Dynaspark. There is some sort of reliability out of those brands...IMO. I prefer the MSD only due to the fact that, when it goes bad, I could mail it to MSD for a 100% complete rebuild for $150 bucks but, other then that, I haven't noticed anything that makes it better then a AC Delco or Dynaspark. The coil conversion seems like something to look into...maybe??

What are the symptoms at high R's?

toptechx6

Check this one out Paul

http://petrisenterprises.com/optispark-distributor/

James93LT1

Was the opti installed in 06 vented?

JimGnitecki

I'm interested in following any Opti discussion.

Jim G

toptechx6

I'll toss this out there for what it is worth since many here are concerned about opti failure, particularly on the early cars.
I have a 93 with about 80K on the clock, to the best of my knowledge the opti is original (it has a Mitusbishi sensor at any rate) I've been collecting pieces parts to change over to the newer pin drive unit should mine fail, but that is a pretty big job just for entertainment.

To complicate matters my water pump recently developed a small leak from the weep hole. Opti is still working fine, I only saw a couple of drops from the water pump, but I did not want to wait for disaster. My (short term?) solution was to replace the water pump and add a drain line fitting to the weep hole. The hose from the fitting extends to the lower frame area minimizing the chance of drowning the opti when the new pump eventually starts to leak from the weep hole.
While I had the pump off, I also installed the MSD 8481 vented cap and rotor kit which includes the vent hose and check valves as a improvement over the stock unvented cap.
Just another option to consider but of course it must be done before your early opti dies. If mine had died I would have made the change to the newer unit.

desertmike1

tough decisions... If I suspected an Opti problem I would at least give it a good inspection, and go from there...

JimGnitecki

This sounds like a well thought out approach.

Jim G

mxw128

Totally agree, in fact that's exactly what I did on my 94. I used the msd vented cap and rotor with a new opti and did the water pump mod with a length of hose running down past the opti:



Don't forget to replace your opti and wp timing cover seals while you are at it.

93LT1

Yes, The Delphi does contain a new Mitsubishi optical. I opened my opti to add thread lock to the rotor threads. I also completely sealed the entire perimeter of the cap and added a vented system. The 96 Delphi vented cap & rotor is an exact fit. I have two new GM none vented Cap & rotors if interested. But I suggest adding the GM vented system with a vented cap.

Tom400CFI

That doesn't fix (or replace) the optical sensor, or the bearing -the two most common-to-fail parts in the Opti distributor. The ignition coil is very rarely the problem.

I agree that a diagnostic process should be followed before throwing a $$$ distributor at it.

JMelton

Never said it was the coil that was the problem, just said maybe it was time to do the coil pack conversion.

Remove the Secondary Voltage from inside the OPTI, and you remove another potential failure mode.

JimGnitecki

Yes, but not the most COMMON failure mode.

Jim G

alscorvette

Under "optispark rework" and then "Corvette Fever" Andy Bolig does a wonderful job of describing what should be done to the Optispark so that it will work. My problem is that it involves the use of a '96 Vauum Hose Harness GM pn 12556174. I have not been able to find this part anywhere. Can anyone help me? Also beside what Andy suggests an additional safeguard would be to change the coil, spark plug wires and spark plugs along with disassembling the distributor and removing the rotor screws and putting Loctite on them and re assembling.If you are over 100,000 miles replace the water pump as well.

mxw128

That's one of the reasons I used the msd vented cap. It comes with the vacuum harness and everything you need. I didn't want to muck around trying to drill out the vent holes in the opti base to install a vacuum nipple etc. I certainly agree with replacing the plugs wires coil etc even before 100k miles. At 77k miles ( or there abouts) I had lost several of the platinum pucks on my plugs and some gaps were upwards of .070"

Strick

The "weep-hole leak syndrome" is a common reason for the failure of the opti-spark. That's why it is a good idea to replace the water pump and opti as a package job. I've suggested this many times before that replacing the OE water pump with an electric pump like the one from Meziere, eliminates the weep hole syndrome and also eliminates a possible oil leak at the water pump drive seal in the timing cover. I've had mine in for over 10 years with no problems at all and mine is the early set up (92). Check out tech tips for how I did the Meziere pump project.

92WhiteVetteGuy

PM sent on new cap/rotors.

pcolt94

This is all true and good advice. However, I was past that point and pretty much determined what the problem was.

This got me thinking or should I say what was I thinking. If it put a cap on, in another 40K I will have 100K on the opti. Better to put a new one in. I would have given the same advice to someone else. I was going to cheap on the repair even though it would have probably fixed it.


The Repair

I cleaned everything that I removed, inside and out. Bolts, throttle body, MAF wires, IAC and seat, air cleaner assembly and front of engine. I spent more time cleaning than removing parts. Also flushed radiator and heater core.

Replaced Opti, water pump, thermostat and oil seals.

The balancer came right off unlike the first time where it took me hours to get it off. It really paid to clean up the surfaces and add some lube to it.

Unfortunately the new pump was bad in some unusual way where it was leaking on the right inside surface. I could not see the cause and it was not the bearing shaft or the gasket mating surfaces. So got another new pump and installed it with no more leaks.

However the next day I drove it I noticed a new oil leak under the engine. I traced it down to the water pump shaft oil seal. Got another seal kit and removed everything again an found the seal got a tear in it when I installed it. Put the new seals in and re-installed it all back on for the 3rd time. This time everything was good with no leaks. Needless to say the original problem is fixed with the new opti and it runs normal.

I was also having the onset of a cooling problem as I could see the signs with the 90* temperatures. So I decided to also clean out the condenser and radiator. But I could not get the air hose down into the areas to blow out the junk. So I (quickly) built a right angle air hose out of a mop stick and rubber hose. Duck tape, 3 hoses, couple hose clamps and all connected to my regular air hose. It worked great as I was able to blow all 4 surfaces very clean. The temperature now does not have the tendency to creep up and it runs the coolest it ever did. I know cleaning was a huge help but don’t know if the new stat was a factor. Now I run below 190 with a air temp of 75 and moving.

Here is my creation to get in between both units. Removed nozzle from air trigger for needed volume of air. (New pictures, photobucket deleted)