well, this is my daughters car and its louder today I found a hole in the exhaust right by the flex pipe(which I think is between the 2 - o2 sensors)
Codes - 171, 300, 302, 304, 306 are showing up. I'm going to try patching the hole today(Sunday) then look for a new pipe.
The front 3 (easy 3) spark plugs are black - sooty and one of the back 3 (the hard ones to get to are looking normal.

When it idles i can hear mis fires as the engine speed varies.

Any thoughts are appreciated.
Jack

 

I would patch the leak first, leaks by the o2 sensor can cause inaccurate reading and mess with fuel mixture. If plugs look crappy then replace them, but only after leak is fixed. I would start there.

 

I cleaned the 3 easy plugs as they were sooty and cleaned the MAF. I also patched a small hole at the "Y" and wala it runs like new again.
Thanks for the help

 

Great! Glad to hear that it worked out.

 

well after a 600 mile trip all went well until now, the exhaust is still good (quiet) but all the codes came back and its runnin rough again???

 

Sounds like what you did before took care of it. Check everything over again, especially those plugs. Make sure your exhaust patch didn't break/leak either. Keep us posted.