986 S problem at idle, engine won't rev and shakes, battery disconnected

[Heiko]

You dont need to take it out, just start and let it idle then start disconnecting one pack at a time (if you unplug one and notice it changes the way the car idles, plug it back in and move on to the next one) You dont have to pull the coil packs themselves out to see if they are working... Just unplug the connector that feeds the coil thats it, you can do that without any tools; If you unplug one and there is no noticable effect at all, chances are either plug/coil is bad.
Just because the plugs are new doesnt mean they are good... I've seen brand new plugs come out of a package that are bad.

[Ghostrider 310]

Seems curious that it documents no codes, it couldn't hurt to toss some Techron injector cleaner and some dry gas too, again cheap elimination of another factor. A careful clean of the MAF couldn't hurt either but you will need anti tamper torx to properly remove it. Don't be frustrated, the problem will reveal itself. I think a bad oxygen sensor could make it run rough as well.

[Gorthaur]

Originally Posted by Heiko

You dont need to take it out, just start and let it idle then start disconnecting one pack at a time (if you unplug one and notice it changes the way the car idles, plug it back in and move on to the next one) You dont have to pull the coil packs themselves out to see if they are working... Just unplug the connector that feeds the coil thats it, you can do that without any tools; If you unplug one and there is no noticable effect at all, chances are either plug/coil is bad.
Just because the plugs are new doesnt mean they are good... I've seen brand new plugs come out of a package that are bad.

Thank you Heiko. Is there any DIY guide on ho to do what you've just described? Maybe here on the board... I'm going to check it out right now.