I know internet is filled with questions like this but I'm out of options so I turned into stackexchange as a great source of knowledge.

So my old green capri has the rough idle.

Car data:

  • Ford Capri mk2 1977
  • V6 Cologne engine
  • automatic transmission
  • Solex carb 32mm EEIT
  • On-engine fuel pump
  • vacuum advance port connected to the distributor

What are the symptoms:

  • when cold it runs good - however, since it runs rough on idle, I had to unscrew the "bypass" on the carb so increase the rpm to 1200-1300 in Neutral/P which results in 800-900 on D
  • when it warms up - say 10-20 mins of running on the highway, when I get to first stop lights you can hear the irregular rpms
  • when running rough, the tachometer shows approx 800rpms but sometimes it wants to die intermittently so it goes down to 400 - it happens approximately once per 10 secs
  • when I press the pedal to accelerate it hesitates for 2-3 secs and goes fine
  • when I press the pedal and immediately release/depress it it will die 8 out of 10 times (this doesnt ever never happen when it's cold)
  • whenever I start it - I have to crank it for 10-20 seconds after priming - it never ever ever starts immediately, unless I went to the shop and came back after few minutes

What was checked:

  • since it's a V6 it has 2 butterflies in the carb and they open simultanously following the same angle
  • fuel filter is brand new
  • fuel pump is brand new
  • new motorcraft sparkplugs
  • fuel lines are heat-insulated with lots of heat insulation hoses as I initially thought I'm getting percolation and/or vapor lock
  • I sprayed around the carb with wd-40 to seek for vacuum leaks but didnt hear the rpms go up
  • the water-choke is working good - takes about 1-2 mins to fully open
  • the distributor looks new inside - it uses the old-style points
  • the coil wasnt checked
  • the ignition advance angle should be good - was set 4-5k kms ago
  • carb was replaced 1000kms ago as the old one was not responding to regulation of the fuel mixture due to clogged fuel tunnels

I'd appreciate any help as this is my daily car. Buying holley or weber is not an option :)

  • Welcome to Motor Vehicle Maintenance & Repair! May 9, 2020 at 1:18
  • Does the carb have a vacuum advance? If so, where is the vacuum line plugged into? Be specific ... Most likely it's plugged into the carburetor, but where on the carburetor? May 9, 2020 at 1:22
  • Dirt in the carb? Perhaps it needs stripping and rebuilding - new jets, seals etc.
    – Solar Mike
    May 9, 2020 at 6:03
  • @paulster2 hi - glad to be here :)
    – wojciechz
    May 9, 2020 at 6:43
  • 1
    Then correct your question, do not leave important info hidden in a comment.
    – Solar Mike
    May 9, 2020 at 6:49


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