So I pulled the opti and replaced it with a Rich Porter one. Has a year warranty, I am thinking what the heck. I will be doing a major rebuild in the not to distant future so did not want to sink big$$$ into a GM one. I will be changing over to the vented style eventually.

So, it goes back together - clean and dry. No fitment issues. It has a vented cap that I cover with a vacuum cap as I have nothing to attach it to.

The car starts fine. When you give it gas it has a pretty significant miss. I marked all the wires and they are on exactly as they were. Of course, no codes thrown.

Thoughts?

 

I know you said the wires are on the way they were,but I would double check them..

 

Ive never heard of that name brand opti and warranty is nothing when if it takes you an afternoon to to replace it or pay a shop to do it for you. GM is the only way to go and you cant find them decently priced on Ebay and on here from the username "thepartsladi" which i believe's name has changed but someone else chime in to correct me. When you buy a new opti you HAVE to rip it apart and locktite the rotor screws and putting diaelectric grease in there and using a bit of silicone on the cap gasket cant hurt it and will make sure no rust or oil is going to enter the cap and cause it to fail.

Those are the first steps to making sure you opti is save and ready to go. Along with putting it and having issues after installation i would double check if your waterpump isnt on to see if the opti is installed properly. Its very easy to screw up to so dont feel dumb if you do its common. Check over your wires for cracks and wear you would be suprised what something so small can have an affect on. Take a look at your Opti harness and see if its corroded which they all tend to be like and clean them up nice or replace the pigtail. Crossing wires will also cause lots of issues aswell so dont feel bad if you cross one it happens were human. Other then that theres not much else you do Opti wise if you still have the missing issue.

There is a right up on www.sshbox.com as to how to diagnose a bad opti, coil, and module to know whats exactly the current issue with your car. Following those steps if your car still isnt running right will get you back up and running again soon.

A properly setup opti after you do all the things above to it should last another easy 100k.

 

Are you sure you indexed the splined drive shaft correctly to the cam sprocket?

 

Fred-

I thought it only went on one way. When I removed the old one, I aligned the key on the new one as it was on the old one. I had to play with it a bit, but it went right on.

 

Unfortunatley, it can be assembled incorrectly, and is done more often than you might expect. Not sure how, but it happens. I've seen numerous posts on this site from people who insisted they installed it right, and argued that it only goes in one way, only to find after checking that somehow they managed to misalign it.

Not saying to did... but just make sure you are confident that you aligned it correctly.

Is it a very specific misfire (like one or two cylinders) or is it just a general roughness in the way it runs?

 

Paul, there is a flat spot on the cam gear and also on the splined shaft,I would take it apart and double check and make sure they are lined up.

 

So I walked away from this for a while...

I started the car today, it fired right up. Its not a miss per-se, but more of a clunk that comes through the shifter. Almost like something is hitting the shifter. I only had a running for a couple of minutes before the clunk(as I will call it) started.