Diagnose:
Motor mounts replaced and firmed up ride and reduced vibration for awhile.
When the car is in D at a stop it vibrates intensely through the steering wheel and in the cabin. BUT no vibe on the center console. Vibrates in R too.
At idle in D no brake it will slowly roll forward with no vibration.
Idle in D it hangs at 500 rpm , in Neutral it rises to 650/700 and the vibration reduces greatly. Highway speeds are smooth, fast and responsive. No slipping or jerking in the tranny during upshifts Sometimes there is a response jerk motion when braking, then releasing and rolling. Like the tranny is catching the engine revs. Happens rarely.
Mechanic stated no codes. The complete drive train is tight and doesn't seem to be worn. -He mentioned possible plug issue. PLugs were replaces about 15K miles ago with Iridium. Coils are original 01,3.0 = 178500K. I replaced the rubber boot throttle body inlet tube and that seem to fix the problem after the mounts were replaced. But now it's worse. I tried running the AC
during testing and the vibration continued the same. I am at my witts end.
What else can I check out that would have an effect on this?
