When coasting in neutral at 15 mph, the idle should be 1000rpm. This insures smooth driveability at low speeds. Idle drops to 750rpm at stop. Check to make sure the driveline is tight. Guibo (flex rubber coupling can crack or disintegrate), half shafts, center bearing, u-joints, transmission mounts, engine mounts. __________________ 1996 Ti 280k miles and still going.... 1993 964 - holding on to this one 2001 Burban, 240k miles 2018 Suburban Z71 |