The car starts and runs perfect. If put into gear, it will run irratic rpms up and down and then stall. If I put it into neutral and let it roll down the driveway before placing it into drive it behaves far better. But, I must drive with two feet and maintain idle speed at 800 rpms in drive when stopped. Then, after 5 min or so of driving it drives perfectly until the next day when started. Any ideas.. 1998 lincoln continental, 90K, always dealer maintained until this - may need to go back, just changed: iac, all plugs and coil packs and coil plugs, air filter, tried a new maf sensor - no help, so returned it, and changed the trans fluid and filter. THANKS IN ADVANCE. Any help would be greatly appreciated!