1) Change your spark plugs, clean/change airfilter, intake tube. make sure hoses are pluged in. There maybe lose vacumn hoses. Check each one.
2) Check PS reservior on driverside behind headlight. Make sure fluid level is OK. Refill otherwise. Check ps hoses. See if ends are oily, possibly leaking. Tighten clamps if you can reach them.
3) Maybe simple as tires are not properly balanced. Put your *best* pair of tires up front. These cars track very well even at obscene speeds!. Rims if non-stock ones may need hubcentric rings. What rims do you have ?. Basketweaves ? If so, are they bent?.
4) REar motor. No hard but lots of stuff to take out. Hydraulics of tailgate : Trunklid shocks are DIFFICULT. Get the dealer to do this, need special tools, not DIY stuff!. The big tailgate hook shocks are exposed, check ends to see if special crimping tool is needed. I got trunklid shocks done at dealer. Took them 2 hrs! Everything off. Works great now.
Good luck.