That helped alot.

Your head gaskets didn't blow. Your Upper Intake Manifold failed, and is still bad. You are fouling plugs with coolant, causing your misfire.

This should tell you everything you need to know:

http://www.bonnevilleclub.com/forum/...e=article&k=38

ok now it is back P0300 and I can not find the problem any idas It runs ruff wen i come to a stop and it feels like it want to move foward..

It is understood that you have a misfire code, but you have to understand that everything you need to know has already been posted here. Did you read everything in the link that willwren posted?

Check your coolant level, is it low?

Yes i did and It got fixed by a coil pack was bad and now its back and every thing is all right coolant is fine and the oil is great no leak in hoses

I don't think you understand. You still have the SAME UPPER INTAKE MANIFOLD on your car? Correct?

You are going to go either BOOM or POOF very soon. You didn't read what we were trying to tell you.

so sorry for not talking sooner but it is fixed and man you have no idea what it was and man you were off track.. it was a plug and a bad wire will post pic of it soon of plug

The very first thing suggested here was plugs and wires...of which you said you replaced.

You're missing the point entirely. Are you still running your old original UIM on the car or not? Do you know how dangerous this is? You are going to suffer from doom and gloom very soon if it is. Every stock OEM UIM on an L36 on this Forum and in the world is on borrowed time. Literally. This isn't an exaggeration.

Dogman... The Series 2 NA motor (the one you have) is known to suffer a failure with the upper intake manifold. While yours may seem to be holding up well, please see the following link in case you car does start to exhibit the symptoms which happen to be close to the ones you had with this thread.

http://www.bonnevilleclub.com/forum/...e=article&k=38