Engine rough when in gear

[rabendan]

My 66 200ci engine runs smooth when in park or nuetral, but runs rough in drive or reverse. I have an autolite 1100 carb and stock dizzy (points). What should I check/adjust first?

 

[woodbutcher]

Vacuum leak,maybe?
Leo

 

[rabendan]

If you mean the line leading toward the vacuum modulator on my c4, it's in pretty good shape. It wouldn't hurt to check and perhaps replace it though. Thanks.

 

[woodbutcher]

Yeah.Should have been more specific.Had that problem on my 74 F100.When the tranny was engaged the motor would move a little,and open a slight crack in the vacuum line.Hope that helps.
Leo

 

[rabendan]

I, too, needed to be more specific. It runs rough in drive or reverse when brakes are applied at a stop. Otherwise, it accelerates and drives well.

 

[woodbutcher]

Start with checking all vac lines.THEN check for intake leaks.Check all screws in carb and carb mount fasteners for tightness.Replace any gaskets that are leaking.Then on to timing.
Leo