1990 FORD F-150 MISS ON CYL. 2 AND 5

  • Tiny
  • Billyboy1983
  • 1990 FORD F-150
  • 250,000 MILES

4.9 ltr. Straight 6 missing on 2 and 5 cyl. Good compression, fire, gas, timing and new computer. Pulled a code 81, air management 2 circuit failure. Any ideas because i've run out. Billy

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Friday, August 23rd, 2013 AT 2:54 PM

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  • Tiny
  • Mhpautos
  • EXPERT
  • 30,743 POSTS

Faulty distributor cap, vacuum leads check these first.

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Friday, August 23rd, 2013 AT 6:09 PM
  • Tiny
  • Billyboy1983
  • MEMBER

Replaced distributer cap, rotor button and all vacuum leads seem to be ok. Still have a dead miss.
HELP.

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Monday, August 26th, 2013 AT 10:34 AM
  • Tiny
  • Mhpautos
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Do you know what the spark voltage is, do you have a good hot blue spark?

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Tuesday, August 27th, 2013 AT 3:18 AM
  • Tiny
  • Billyboy1983
  • MEMBER

I have a blue spark on all cylinder's.

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Tuesday, August 27th, 2013 AT 11:36 AM
  • Tiny
  • Mhpautos
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I feel that there must be a vacuum leak affecting these cylinders, ensure that this is not the case first.

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Thursday, August 29th, 2013 AT 2:45 AM

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