Vent Tube Carb Stuff
Sam 1988 Vent tube service note:
Do'n know who but some one posted awhile back that they
installed Ebay vent tube in a Sam and had performance problems.
This vent tube stuff my help you out.
I also installed Ebay vent tube Sam ran great for two
weeks, but then engine began hesitate momentary and lack
power most noticeable on stopping and starting.
Kind'a like engines vacuum advance hose bad leak in hose.
Suspected vent tube came loose or rotated or something
mine was loose fit, had to fix it in place with a dab of
high temp silicon. Check vent tube and it was fine.
OEM service manual page2-4 trouble shooting listed symptoms
as faulty idle switch on carb, so i checked switch, found
problem to be bad faulty idle micro switch on carb.
Switch was stuck, sending a constant signal to ECM that
engine should be at idle, even while trying to drive
60 mile hr. down interstate.
Replaced with radio shack micro switch problem fixed.
Believe micro switch was intermittently failing and over
period of months, believe vent tube engine performance
upgrade increased carb sensitivity amplifying what was once
a not so noticeable condition.