Erratic idle

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Joe Dirte

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98 k1500 305. Started to have a slight bounce in idle a few weeks ago. Took it to get beer n smokes other nite n would barely run. Almost died at stop light. Gets up around cruisin idle its not as noticeable. Had a full tune up this spring with plugs wires cap rotor n filter. Previous owner did new pump before I bought it. Fire it up n it fights to idle and bounces from 200 to 900 rpm in park or in gear. I'm planning to LS swap it in spring but would like to have it driveable incase get a bad snow over winter. Any ideas where I should start looking?
 

df2x4

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I had a similar issue in my red '97 once. It ended up being a cracked vacuum line.
 

Joe Dirte

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I had a similar issue in my red '97 once. It ended up being a cracked vacuum line.

Waa actually bout to go out n check em. U just happen to see it or did u spray some carb cleaner while it was running?
 

df2x4

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Waa actually bout to go out n check em. U just happen to see it or did u spray some carb cleaner while it was running?

Neither, my lazy ass drove it to my mechanic. :lol:

If I recall correctly I think he did a visual inspection and found a pretty large crack. Sorry I'm not more help!
 

Urambo Tauro

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Definitely start with easy stuff, like checking vacuum lines. Mine didn't go away until I put a new distributor in it.
 

Joe Dirte

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Did a visual and all vac lines looked fine. Pcv valve noisy as hell. Cleaned it out til I get to town for a new one. I mite pull cap tmrw n see if shaft has too much play or corroded bad
 

jsfrmsj

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Might be worth a shot to clean the IAC with some electronics cleaner, its the smaller sensor on the throttle body. 2 T20 torx screws and its off, only takes 10 minutes.


Edit: Nevermind I thought you had a 350, I'm not sure where the IAC is on the 305
 

Joe Dirte

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Might be worth a shot to clean the IAC with some electronics cleaner, its the smaller sensor on the throttle body. 2 T20 torx screws and its off, only takes 10 minutes.


Edit: Nevermind I thought you had a 350, I'm not sure where the IAC is on the 305

Believe it should be in same place. Heading to class so that's something else I'll look into. Thanks.
 
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