stutter?

[nwmod39]

i recieved a 1986 k-20 pickup from my fathers passing and it was not quite up to tune when i picked it up. upon tearing into the tune up i found that three spark plugs were only thread into the cylinder head half way as well as a worn out distributor, 2 burnt plug wires, leaking water pump, and carb studs that were barely thread into the intake leaving the carb only finger tight.

now that i have the tune up complete it runs great except for a small stutter when it is in park idling. right now i have the timing set at 8 degrees and it sits at 690-710 rpms idle.

occassionally it will stutter or die out for a second and then resume a solid idle for a minute or two. the truck runs fine down the road at this point but i will be most likely be going with a new carb and a spring kit for the hei.

anyone have a clue as to what would cause this.

also is this truck new enough to have the esc on it. i have a bunch of connectors sitting on the intake near the carb with nowhere to go.?

[Prerunner1982]

yes it should have esc, i believe that came out in 81, or atleast 82 as my 82 has it.. as far as the stutter.. you might turn up the idle just a hair and see if that helps any. As long as the truck doesnt die i wouldnt be all that worried about it.. unless it really just hiccups and almost stalls.. My wifes 87 has a slight miss at idle, but i havent tried changing plugs or wires or anything on it yet..

[beaterC10]

A vacuum leak, worn out distributor, or maybe a worn timing chain might be the culprit. My money would be on a vacuum leak.

[nwmod39]

my vacuum gauge installed on the full port at the base of the carb is reading15 inch (17.5 ibch if the directions are correct to adjust up one inch every one thousand feet of elevation above sea level.

the distributor is brand new with the rest of the tune up so its not worn out.

it is not really having any affect on the drivability or anything its just something that gets to me when idleing at a stop.

[beaterC10]

Did you check all the underhood vacuum lines?

[nwmod39]

only vacuum lines i have go from the hei to the carb(currently plugged) and the 3 at the back of the carb ( power brakes, trans mod, and the third i do not recall of right now) which are all good.

are you familiar with any of the esc plugs?

[82c10]

Originally Posted by nwmod39

only vacuum lines i have go from the hei to the carb(currently plugged) and the 3 at the back of the carb ( power brakes, trans mod, and the third i do not recall of right now) which are all good.

are you familiar with any of the esc plugs?

you probably want to hook that one back up for your vacuum advance

[nwmod39]

i will in time. i was going to do a baseline for my hei springs and move on to the vacuum advance after that is complete.

[beaterC10]

Originally Posted by nwmod39

only vacuum lines i have go from the hei to the carb(currently plugged) and the 3 at the back of the carb ( power brakes, trans mod, and the third i do not recall of right now) which are all good.

are you familiar with any of the esc plugs?

There should be two, a four or five pin plug that has the green rubber seals and a single power plug. You can ingore them if you have a non ESC hei.

[nwmod39]

the single power plug that goes to the bat terminal on the distributor is a dual plug. one going to bat terminal and the other going to the tach terminal. if i have all the esc disconnect can\should i unplug the tach terminal?

[79BIG10]

Check here for some info on the ESC removal while keeping the distributor in the truck. http://73-87.com/7387garage/drivetrain/escrepl.htm

[nwmod39]

excellent!
thank you
steve