You sure co adjustment is going to fix that? I've not seen one doing that consistently....... ever.
Anyway, you get the engine warm, remove the cap from the diag connector on the l/f fenderwell, hook a DVOM that is set to duty cycle to pin #3, positive, ground to the engine, 3mm allen in the adjuster (might be plugged, remove that) press down and turn clockwide to richen, counter to lean. You should see a duty cycle of 40 -60% with a swing of 5% or so. (it's following the o2 when it swings) Fixed cycles are indications of a failure and need to be addressed first.
You say it didn't start until after the pump and filter were changed? I wonder if they installed a bosch fuel filter, I has a bunch of those several years back that the paper exploded in as soon as they got hit with the gas, did a fine job of trashing the fuel distribitors, never had a knetch do that.
early 119's also have split ign systems with 2 caps, rotors, coils and EZL's, I'd look hard at secondary ignition while I was in there.
Project Smoker, '87 603 powered wagon
Hauler, 96 CTD can you say torque?
Toy 73 Cougar xr7 convertible
Acme Automotive Inc.