350 high idle

[Crob]

My 82 K15 has a 350 in it.  The thing is, it will idle high until it gets warmed up, after you give it a little rev it will run like normal.  How do I get it to just idle normal after i start it?

[txchainsawgogi]

choke plate sticking? choke coil wound properly? are you sure the idle calms itself after warming up or after you've been opening the throttle? it could be a needle not seating correctly and after giving it gas it sits how it should.

[greenmonster]

There is a screw on the carb linkage to adjust the high idle.If you back it off to much,it may not idle when its cold.My truck idles at about 1200 rpm at hight idle.

[bake74]

     What do you mean high idle ?  (what rpm), both answer's are correct.  Your engine should idle high (1000 - 1200 rpm) until either the choke warms and shuts off the high idle cam on the carb or like stated you hit the pedal to reset the high idle cam.
     I am assuming your carb has an electric choke.  There is adjustments on the idle cam on the carb and mentioned, on warm days after you already started it, it should not idle high.  But on cold days it should always idle high unless you drove it already and it has not cooled back off.
     You said you hit the pedal and it idles fine.  Is this right after starting or after a couple of minutes ?  Or will it high idle all the time until you hit the pedal ?  More info is needed for right diagnosis.

[Crob]

There is no tach in it so i cannot tell you the exact rpm, but It sounds like 1000-1200.  If I start it up and hit the gas right after I start it, it will stay running high.  When it gets warmed up and I hit the gas it will go down.  But it does not go down without hitting the gas, it continues to run high. If that helps.

[jaredts]

Sounds like normal operation to me.  If you think its too high back out the high idle screw as mentioned.

[bd]

There is no tach in it so i cannot tell you the exact rpm, but It sounds like 1000-1200.  If I start it up and hit the gas right after I start it, it will stay running high.  When it gets warmed up and I hit the gas it will go down.  But it does not go down without hitting the gas, it continues to run high. If that helps.

Sounds like normal operation to me.  If you think its too high back out the high idle screw as mentioned.

I think jaredts summed it up rather nicely.   

[sbx22]

I agree, that sounds normal.

[bake74]

There is no tach in it so i cannot tell you the exact rpm, but It sounds like 1000-1200.  If I start it up and hit the gas right after I start it, it will stay running high.  When it gets warmed up and I hit the gas it will go down.  But it does not go down without hitting the gas, it continues to run high. If that helps.

Sounds like normal operation to me.  If you think its too high back out the high idle screw as mentioned.

I think jaredts summed it up rather nicely.   

      Just another vote that is sounds normal.  Even newer cars take a while to come off high idle when it is really cold outside.  Though I would think that eventually it would come off by itself.  You might want to check the plates that txchainsawgogi mentioned if you can, they might be sticky.
     But for the cost of repairs if you do not do it yourself, you could live with it until the carb. needs rebuilt.

[joel]

I always let my 86 warm up since its cold weather.(Ride to the bus stop) It seems to idle up then i have to give the pedal that pump to idle down.  10 mins or so. Mine idles what i call high but that is probably the way it came and is supposed to act.  As long as it acts the same way every day and doesn't interfere with the initial shift into gear, be glad you don't have to baby sit in the cold.