:?: When the engine is cold it runs perfect. Lets say i am going along the highway and wnats to accelerate hard. Then one or maybe two plugs/ cylinders wont work. The engine starts to studder it will not rev up. I ahve had it to a garage where they changed a solenoid in the transmission but they also told me that one of the coils were bad and by the way they also changed all the ignition cables. Everything was Ok but now i have the same problme all over again. I do not know what to do. Can somebody give an idea on what is going on here. Like i said it runs nice and smoth but if slam the pedal the engine wil not respond.

How far back did the garage work on it?

Did they change the bad coil(*)? The coil towers corrode and cause a high resistance in the secondary ignition system. New wires alone will not fix the problem. You need to replace any coil packs that have corrosion as well.

One coil was changed, i think about 3 years ago. It seems like you think i should change all of them to get rid of the problem. In that case where should i go to buy a new set?
$$$$?
And by the way do you know why the engine is running good when i dont accelerate?
Thanks for these answers by the way!!!

Does it run OK at regular highway speeds?

You say that it is stuttering when under WOT. It'* not just bogging down, but specifically mis-firing?

Yes it does, it starts to missfire if i do a kick down. This is happening all the time especially if i am in overdrive and lets say i get in to a hilly area going up hill for instance. You know you want to keep the speed compenasting with gas. Then at one pont the engine acts up. I almost have to shift manually.

I assume you are not getting any SES/CEL light or you would have said so....correct?

Do you have tools and are doing some work yourself or will you be taking it back to a shop for repair? I ask since it will make a difference what we recommend.

If you want to check some things for yourself first, check your coils per this article:

Ignition Coil Troubleshooting

You are totally right, no lights no nothing. And yes i do have the gear to do most of the things myself but you know how it is with electrical problems. Those things could lead you anywhere. At least thats my experience.
Another thing is also that i am from Europe and have no whatsoever experience or knowledge about american cars and their specific problems.

Do you have a multimeter to do the coil check?

Yes i do. I also checked that file extension or link you sent. The only problem with that is that my coils doesnt look like on the pictures. i have a differnet package with 6 individual coils i could take a coupple of pictures and show you?