Jumping Idle

1979 FORD THUNDERBIRD
48,765 MILES
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SHAZAM5088
  • MEMBER
  • 2 POSTS
The idle on my car randomly jumps from 500-1200 at strange times. It can last several minutes or up to an hour. the it goes back to normal idle. No pattern to when or why this happens. The car has a 351M.
May 23, 2013 at 2:33 AM
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SINBAD271
  • ✓ASE Certified Mechanic
  • 169 POSTS
  • ASE Certified Mechanic
Has your car been serviced lately ?
May 23, 2013 at 5:30 AM
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SHAZAM5088
  • MEMBER
  • 2 POSTS
New cap, rotor, fuel filter, coil, plug, wires. It still jumps
May 23, 2013 at 2:39 PM
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SINBAD271
  • ✓ASE Certified Mechanic
  • 169 POSTS
  • ASE Certified Mechanic
Check all vacuum hoses ,make sure none are torn ,split,or disconnected., check intake manifold gasket for a leak.
May 23, 2013 at 8:32 PM
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