I've got an intresting vibration that has developed in my 4.0 after completing a recent header and engine mount upgrade. When at idle and in either drive or reverse there is a significant vibration that develops throughout the vehicle. Shakes pretty bad, vibrates mirrors and steering wheel. When under the vehicle the exhaust looks like it vibrates about an inch either side of center. The funny part is once the engine warms up the vibration decreases significantly. There is no issues while in park or neutral and there doesn't seem to be any trouble with the engine. It seems to be idling smoothly at about 800rpm. And the moment I add a little power the vib goes away completely. And I'm using rubber mounts not poly.
What I've tried. Through research and trying to eliminate possibilities.
Burned 2 cans of carb cleaner searching for vacuum leaks. -> none found.
I have tested fuel pressure as I had recently also changed out the fuel pump. -> pressure normal.
Plugs are pretty new. And coil pack is only a year old.
Torque on new engine mounts seem good.
New steering pump, cause it seemed to be worse when at top center steering. ->no change
This weekend I'm going to swap out the fuel injectors to 4 port A-6 units. I was planning on doing this anyway, but maybe it could help my vibration issue too.
Any other ideas that anyone can think up? I'm at a loss on this one.
Thanks for your help.
What I've tried. Through research and trying to eliminate possibilities.
Burned 2 cans of carb cleaner searching for vacuum leaks. -> none found.
I have tested fuel pressure as I had recently also changed out the fuel pump. -> pressure normal.
Plugs are pretty new. And coil pack is only a year old.
Torque on new engine mounts seem good.
New steering pump, cause it seemed to be worse when at top center steering. ->no change
This weekend I'm going to swap out the fuel injectors to 4 port A-6 units. I was planning on doing this anyway, but maybe it could help my vibration issue too.
Any other ideas that anyone can think up? I'm at a loss on this one.
Thanks for your help.