HardcoreRM125

The car has 14,000 origional miles on it. The Opti however, may not be origional, the car was totalled, and I bought it that way with a truckoad of parts ... So its possible the Opti is older. For the past 1000 miles I've put on the car, the waterpump has not leaked a drop onto it.

At first it was a slight miss that went away past Idle. Worked itself out. Then it slowly started to come back. It's intermittent, and it getting worse very fast. I thought it was my wires, cause at night you could see SLIGHT archs at the boot where it goes on the plug, but I later noticed it arching all around the Coil too I replaced one plug wire which didnt seem to snap in as tight as the others, and just re-dielectircal greased all the plugs and wires including the Opti end as well as the plug/boot( Also got the Coil plug, and electrical connectors). The plugs are old, but low mileage on them. Its not like they go bad just sitting somewhere, and when I pulled some of them a week or two ago during my header install ( Miss was there before headers BTW, NO wires are burned ) and they were clean looked like new. The miss seems to get worse now everytime I drive the car, im afaid to take it somewhere and have it die on me now.

Strangely, it misses MUCH worse under a load. Any hill at all, I need to downshift so im over 3000RPM's otherwise it misses so hard it actually starts to loose RPM's. On the level is misses, but no where near as bad as going up a hill. In nuetral, it seems to Rev fine, like its not missing at all.


If I punch it on a level area, it misses like crazy till 2500RPM's then stops, and pulls, but not as hard as it should. What else can it be besides my Opti ...

The wires ARE all in place rite, and properly connected to the Opti.

Also it misses MUCH less when its cold, but after 2 minutes of driving

To sum it up if you dont want to read the book I just typed:

~Wires SLIGHTLY arched at plug boots, so I dielectrical greased them and the coil wire/connectors.
~Miss WAS intermittant
~Miss gets worse every time I drive it
~No wires are burned
~Plugs are older, but low mileage, and look fine/clean
~Wires visually look fine, no cracks or anything like that at all. The wires arent arching anywhere except the boot end the plug is on, and its very slight
~Miss isnt too bad on level roads, but noticable
~Gets WAY WAY worse under load ( Hills )
~Goes away or so it seems at around 2500 3000 RPM's, but still doesnt pull like it should.
~Miss gets MUCH MUCH worse as it warms up.


So help me out guys, what else could it be if its not my Opti? I dont want to spend a ton of money on a Delteq if I dont have too...

Also I remember a while back someone had a write up on how to check the opti, that would be awesome, but I dont remember who had it on their site

HardcoreRM125

Also ... I forgot to mention ... Sometimes if its missing, If I let off the throttle completely, then ease back into it, it will pull like normal for a few seconds before it misses again.

HardcoreRM125

Anybody ???

1fast95Z

Sounds to me like an O2 sensor.

HardcoreRM125

Really .. ??? How can I check them ? There was a miss BEFORE the header install, and it WAS getting progressively worse BEFORE teh headers, after the headers, nothing has changed, still gettin worse and worse ... How can I tell if its an O2 without having to buy one ?

HardcoreRM125

Also ... When I did the headers, I DID NOT get new O2's ... The O2's had a vert thing layer or carbon on them, like any exhaust component. All the little luevers in it for Air to go into, they were all clean/open ...


I never even thought of O2's ... But this may help confirm if it is or not ... The car DID sit from 1996 ( When it was totalled with 13K miles on it ) untill this past August once I got it running, but then had to wait MONTHS for paperwork for my title. This is the most the car has been driven recently.

Thanks for the suggestion, now to find out how to test em without buying new ones.

Rezhalo3

Wow that sounds exactly like one of my problems. I have a million oil leaks so I have reason to believe that my problem may exist in the rings (compression ring).

But I just got the car and went to do emissions and it did not pass so my problem may also be O2's. Let me know what you come up with.

HardcoreRM125

Anyone ??? Could it be the O2's ... I NEED my car fixed ASAP, and dont know what to try next since it apparently IS NOT plugs or wires ...

mzgp5x

I had two of the opti-spark break. The arcing is typical of the opti rotor destruction. I bought a new opti, and it happened again. Same thing. Dissection of the opti revealed the rotor destruction. With a high energy spark (MSD), the rotor heats up (copper) and melts the plastic buttons. Rotor explodes, or copper comes loose. The remaining part of opti was OK. Just the rotor sucks. This was a new gm opti and it did not last 1 month. New project, design and machine new rotor for opti. Beware of opti!!!

shoebox

Typical of a spark problem to be worse under a load, just as you described. Could be coil, coil wire, opti, plug wires. If you have no trouble codes, it's probably spark related.

HardcoreRM125

Ok thanks Shoebox, is there anyway I can test the Opti and the Coil ? Im sure the coil you could jsut check it with a multimeter somehow, theres not much to a coil I think

Also if its the Opti, what is the best replacment, A Dynaspark? How do these work, How much, and where can they be ordered...

As far as a coil, what would be a good coil to pick up for a lightly modded, near stock, car? I dont want anythin that will burn up the Opti like mzgp5x's.

mzgp5x

I have an ati D1 blower running 15 psi. I need a hot spark and I like the tripple spark CD feature (to 3K rpm) of the MSD unit. I also run a 8202 blaster coil and a variable timing unit to dial in timing. You can run the Delteq ($500-$600). It will splice between the gm opti. When you get your opti off, shake it to see if there is loos debries floatin. I so, take apart and remove debries. You still need the opti o run Delteq. You can't run all the MSD CD stuff on a Delteq due to the multiple coils. You also will need to run new wires from your muti coil unit since you require re-mount location. I am building a new rotor for the old opti. More involved than I though, but making progress. Maybe I should start my own opti-fix bizz!!! Ha. There is a web site shbox.com for diag instructions on the opti.

shoebox

There are some tests for the opti and coil on my page, but they probalby won't do anything for you particular situation. A Dynaspark is just a glorified opti. It may have a couple of beefed up items and may seal better, but it works just the same.
I personally believe that the plug wire terminals inside the opti can/will continue to corrode during non-use, so that could be a problem for your old opti. You should also check the opti electrical harness for corrosion.

I would consider changing your O2s as well. If you had them in there during new header burn-in, they may be fouled.

No harm in running an MSD coil or box like the 6A and it's variants. Myself and others have logged thousands of miles over many years with this equipment with no adverse effects.