General Maintenance & Repairs - power loss

im having a lil bit of a prob. w/ my 02 ws6 -m6 for some odd reason my ses light came on and stayed on for about 2-3 months then all of a sudden it went off but now the car runs like sh#t. the car ran the same w/ the light on but since it went out it seems like the car doesnt pull as hard as it should unitl it tachs about 3 grand and up but if held at high rpms for a lengthy amount of time it starts breaking but spitting and poppin and the valves have become noticibly louder when rpms are up The car has 106,000 miles on it but i just put new plugs in about 6,000 miles ago the car still has the stock tuning


does this sound like the plug wires or the fuel pump /filter or maybe a weak or bad coil???

im thinking about going w/ msd wires and coil
I've seen the new lsi coils from Msd but cant find a price has anyone tried or heard anything about them???


any suggestions?????

1st Step: Find Out What the Code Was.
2nd Step: Troubleshoot the code.

Or:
Shotgun Approach:
Replace the motor, one piece at a time, until the problem goes away. Start with the wires and plugs, then the coils, then the heads, then the block, etc.

The code could be caused by almost anything, which means your problem could be caused by almost anything. Have it read and that will give you an actual starting place.

You got to get that code read...cruise down to autozone they will let you borrow a reader for free.