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...strange problem.

   
Old Aug 9, 2012 | 11:20 PM
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PatientZero's Avatar
PatientZero
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...strange problem.
Okay. I'm working on my 1978 f100 with a 300. Auto transmission and original Carter yf. Carb. Truck runs like a dream in park or neutral, but as soon as put into gear, it idles way too low and backfires through the Carb when given gas. I've replaced plugs, wires, coil. Rebuilt carb and changed manifold gaskets. Adjusting timing doesn't seem to be helping any. Does anybody have any ideas about what i may be missing?
-patientzero
 
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Old Aug 9, 2012 | 11:24 PM
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devino246
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Start checking all your vacuum lines. Sounds like a vacuum leak.
 
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Old Aug 10, 2012 | 07:13 AM
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fmc400
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Agreed, sounds like a vacuum leak. I'm also going to assume that when you adusted the timing, you used a light and NOT by ear.
 
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Old Aug 10, 2012 | 10:46 AM
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Rusty_Old_F250
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From: Western Washington
Check your booster, get a pair of vice grips and use them to clamp them onto the vacuum line for the booster then test drive it.

Sam
 
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