To start off i have a 97 lt1 that i have put long tube ceramic coated PS's.MSD 8.5 mm wires, ac delco plugs, O2 extensions up front and o2 sims in rear. I took the car out for the first time and my check engine light came on. i took it to autozone and showed bank 1 o2 no activity they said. The car was running fine started right up ran good. On the way home thecheck engine light started flashing and then the motor ran rough as all hell. i shut it off for a couple of minutes and made it home. it wouldnt run good, boggin out. what could it be? havent got a chance to make it to get checked.

 

Check to make sure you didn't burn an o2 sensor wire, or any other wires for that matter. Perhaps an o2 extensions is defective.

 

Check to make sure the harnesses are in good shape. Also, you can try swapping 02 sensors from bank to bank and see if the code follows, then you can rule if the sensor itself is bad or not.

 

I believe bank one is drivers side. If it worked for a while and then showed no activity then i would guess it is burnt or connect came loose.

 

would that cause the engine light to blink then run rough after driving for approx 15 min. . i stopped the car and popped the hood and the motor was literally shaking. I have never experience that from a bad o2. Car starts right up even right now and idles good. after driving it for 15 min the light blinks and runs rough.

 

A dead cylinder. A flashing SES means you have excessive missfires/dead cylinder. Because you have just put headers on (I guess that's what you mean by "long tube ceramic coated PS's") you need to re-check ALL wire routings to make sure no wire, including plug wires, are touching the headers in any way.

 

is it a easy fix or major?

 

You need to find out if you burnt anything. I'm betting with the new found problems you've had with missfires and no 02 activity you've fried a few things. Before you start it up anymore you need to either have it towed to whatever shop did the headers for you, or if you did it yourself you need to check all wires carefully. You don't want to drive it any more and cause more damage to any wire harnesses or plug wires than what might already be damaged.
If you find a plug wire that is burnt. It needs to be replaced. If you find other harnesses burnt/damaged they need to repaired.

 

Get the codes pulled again. It might pinpoint the cylinder(s) where the misfires occur.

 

once it pin points i know to check that plug /wire