The last 2 days my girlfriends car has been hesitating when you are driving at about 30 mph 1,500 rpms. You can feel the tranny and or engine shake the car. You lift on the gas pedal and it stops and if you keep driving will do it again. We hooked it up to a diagnostic computer and it didn't show anything. The mechanic said to tune it up and that he had a Lexus 2 weeks ago and thats all he did and it had similar issues. New plugs, wires and rotor cap and it still does it. We could see on the back of the intake where 2 of the plug wires were arching against it. Kind of out of ideas and dont want to wait for it to blow up. If you drive the car fast and keep the rpms up it doesn't seem to have the issue.

2003 Galant
65,000 miles
Automatic
Think it has the 3.0

Thanks

 

Check the coil pack and stop it from arcing. Its doing that because not enough current is getting to the plugs causing a little misfire.