idle issues, transmission failure '97 328I

[tycapps4]

I recently replace my valve cover gasket, and ever since then my car idles around 400 and shakes violently. sometimes it stalls completely. The car does not accelerate as fast as it used to, also if i am in a high gear at a low speed, it used to steadily pick up speed, but now i shakes and feels like its going to stall. i tighten the spark plug covers and made sure the maf sensor was plugged in. Check engine light is on. please help!

[bostogrun]

Whats the light say? If you don't a code reader go to Autozone, they will read it for free. The access is behind a rectangular cover under the dash on the drivers side. 99% chance its going to be PO 3OO something i.e misfire cause by a coil pack issue.

The only thing you could have messed up would be the coil packs. Are they all hooked up, are plastic boot tubes properly seated on the plugs. Did you forget to connect the coil grounds?