Confused about stuttering
03-17-2016, 02:35 PM
#1
Confused about stuttering
I recently change my 2 front motor mount and transmission mount. Now my truck is running rough and has lots of vibration while driving. No engine codes, all vacuum lines and connectors are good.No fuel line leaks. Scanner shows all system parameters are good and within spec. MAFS clean and within volt. specs. EGR good. PCV good. Really confused.
2003 4x4 automatic 5.4l with a/c 6" fabtech lift with 35" tires.
2003 4x4 automatic 5.4l with a/c 6" fabtech lift with 35" tires.
03-18-2016, 01:52 AM
#2
Senior Member
The engine runs rough SINCE you swapped the motor mounts? And you did nothing else? My guess you knocked something while doing the mounts.
Why did you change the motor mounts?
An old trick to look for vacuum leaks is take a spray can of carb cleaner and spray around any and all vacuum lines, one area or line at a time. Wait a few seconds. If the idle doesn't smooth out or go up, that area/line is fine. If the idle does go up or smooth out, there's your leak.
How are your plug wires?
Start with the simple/cheap things first...
Why did you change the motor mounts?
An old trick to look for vacuum leaks is take a spray can of carb cleaner and spray around any and all vacuum lines, one area or line at a time. Wait a few seconds. If the idle doesn't smooth out or go up, that area/line is fine. If the idle does go up or smooth out, there's your leak.
How are your plug wires?
Start with the simple/cheap things first...
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Ronnie Mullaley (03-20-2016)
03-20-2016, 11:10 PM
#3
No leaks. All sensors reading within spec. Plugs, wires, coils and connectors for spark and fuel good. Going to check fuel pressure tomorrow. If that comes back good, I'm calling our lead mechanic at Ford.