Last year, I spent a lot of time cleaning up my engine. Part of the process was to relocate my Crane ignition box to the interior on the firewall. I also cut off the plug that leads to the Opti-Spark and hard-wired the wires together (to get rid of the big plug). Not the plug that goes into the Opti-Spark but the quick disconnect that is on the passenger side of the intake manifold. Before I did all of this, the car ran very good. Now, after everything was done, it has a bad misfire only around 5,800 rpm. The car pulls very hard up to the RPM.

I don't know if it is the Optispark, but I would like to examine all other issues first.

I did try to replace the coil, but it was fine. I also looked at the plug wires and put in frest plugs, and the problem is still there.

Here is how I wired up my ignition box in the interior. I took the white wire that comes out of the tach filter and the white wire that comes out of the ignition coil module, and hooked it up to the white wire on the Crane box. I then took the the pink wires and hooked them up to the red wire on the Crane box. I then ran a heavy gauge wire from the Crane orange and black to the coil.

Do you think that my problem could be in either the wiring that I did for the ignition or the opti spark? I did add length to the igntion wire but not a lot and I increased the gauge size.

Is there a way to test the voltage to both components?

Any help would be appreciated.

I would try to replace the opti but I am also planning on doing a cam swap and I am going to have the car dyno tuned by Pcmforless in April. Because of the cam swap, I won't be able to drive the car hard to see if I solved the problem because the car will need tuned. Then, I don't want to be at the dyno tune to find out that the opti wasn't the problem because this is probably the only time that pcmforless will be in my area to tune.

 

i'm not much on chasing electrons and what not, but i believe when you change lengths and diameter of a wire you change the resistance values. also, your connections could have also changed resistance values. i would at least look into that if the prob started after your wiring job. if know one on this site knows, then talk to someone in your area who chases electrons for a living or check the dealer. always good to have an insider at the dealer

 

Thanks deputydough, I was wondering if the opti and the ignition coil are looking for resistance like you mentioned. I would think the coil is only looking at voltage but I would love to confirm.

Any other help?

thanks

 

If you used the same size wires for the "lenghtening" process, you'll be OK. Electrons DO get slow (resistance increases) with long/skinny wires, but unless you're running a tuned circuit, they have to be REALLY long/skinny. You mentioned you "hard-wired" some of the leads... you could have a cold-solder joint. This is kindof common (especially if you don't have a lot of experience in soldering). Basically you end up moving/allowing motion of the wires BEFORE the solder hardens, and you end up with something that looks good on the outside of the solder, but in actuallity the wires are not getting a good connection (read a high resistance). If in fact you did solder some wires, one of the things would be to go back and re-heat the connections. Make sure there is NO movement on either end until the solder cools. Don't know if this will fix your problem, but it will eliminate a potential one. Good luck.