what would cause my motor to shake

1999 FORD F-150
16,500 MILES
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AZFIREWOMEN
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  • 1 POST
under load thr motor shakes but smooths out about 65mph. there is a hissing sound at the back of the motor and the service motor soon light came on.
Jun 12, 2012 at 11:04 PM
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ASEMASTER6371
  • CAR REPAIR CONTRIBUTOR
  • 52,796 POSTS
there is an elbow for the pcv valve on the back of the throttle body that collapses and causes this condition.

Roy
Jun 12, 2012 at 11:16 PM
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RASMATAZ
  • CAR REPAIR CONTRIBUTOR
  • 75,992 POSTS
Sounds like Mr. Roy is on the money here-Excessive false air leakage-Scan the computer for code/s, lets see what it has to say
Jun 12, 2012 at 11:40 PM
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