I hope this is in the right part of the forums has been some time since posting here. I have a 2003 Grand Prix GT four door. When driving i get engine compartment vibration at 4000 rpm and also when letting off the accelerator at around 50-60 rpms drop way low to around 900-1200 or so and don't seem right. Just curious it also has the imfamous problems with abs and tcc but thats a problem i know what it is and not really worried about it.

Thank for your help.