# 1995 S10 Blazer high idle speed (vortec 4.3)

**URL:** <https://community.cartalk.com/t/1995-s10-blazer-high-idle-speed-vortec-4-3/15306>\
**Category:** Maintenance/Repairs\
**Created:** [June 14, 2008, 11:59am UTC](https://community.cartalk.com/t/1995-s10-blazer-high-idle-speed-vortec-4-3/15306 "2008-06-14T11:59:02Z")\
**Posts on this page:** 5\
**Page:** 1

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**Author:** ![GSragtop](https://avatars.discourse-cdn.com/v4/letter/g/7c8e57/32.png) [@GSragtop](https://community.cartalk.com/u/GSragtop)\
**Post date:** [June 14, 2008, 11:59am UTC](https://community.cartalk.com/t/1995-s10-blazer-high-idle-speed-vortec-4-3/15306/1 "2008-06-14T11:59:02Z")

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Hey Gang,  
  
  
  
 I just purchased a 1995 S10 Blazer with the Vortec 4.3 V6 the other day. I got it running very poorly back fireing thrugh the exsaust lightly (poping), etc. After reading around the internet I figured it was the Spider (CPI injector). So I took off the upper intake, and found that the Nut kit (the fuel lines running into the injectoer), were leaking badly and dumping fuel into the manifold. OK so I replace the Nut kit, and bit it back together. Now the truck runs great, nice and smooth. However it idles at around 2500-3000 RPM, and will not come down. The previous owner replaced the EGR valve (with a used unit)and the fuel pump. I tryed unplugging the EGR valve, and that did nothing. I double checked my work looking for Vac leaks, and could not find any. Also I think it idled fast before the work as well.  
  
  
  
 What is my next step??  
  
  
  
 Thanks

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**Author:** ![GSragtop](https://avatars.discourse-cdn.com/v4/letter/g/7c8e57/32.png) [@GSragtop](https://community.cartalk.com/u/GSragtop)\
**Post date:** [June 15, 2008, 1:53am UTC](https://community.cartalk.com/t/1995-s10-blazer-high-idle-speed-vortec-4-3/15306/2 "2008-06-15T01:53:23Z")

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bump

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**Author:** ![GSragtop](https://avatars.discourse-cdn.com/v4/letter/g/7c8e57/32.png) [@GSragtop](https://community.cartalk.com/u/GSragtop)\
**Post date:** [June 16, 2008, 1:57am UTC](https://community.cartalk.com/t/1995-s10-blazer-high-idle-speed-vortec-4-3/15306/3 "2008-06-16T01:57:25Z")

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Well Today I pulled the IAC valve, and shot it with some wd40 to clean and lube it. re-insaled it and the idle slowly cam back down to 1000 RPM. Great I figure the problem is fixed, and I turn off the truck so I can change the oil. Finish that job, and go to re-start the truck and now it will not idle at all. If I put slight pressure on the gas pedal it is OK, but as soon as I lift it stalls gain. Im thinking it is a bad IAC, but its $100 for a new one and that is an expencive shot in the dark…

What do you guy think\>?

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**Author:** ![GSragtop](https://avatars.discourse-cdn.com/v4/letter/g/7c8e57/32.png) [@GSragtop](https://community.cartalk.com/u/GSragtop)\
**Post date:** [June 16, 2008, 8:40pm UTC](https://community.cartalk.com/t/1995-s10-blazer-high-idle-speed-vortec-4-3/15306/4 "2008-06-16T20:40:39Z")

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bump…

Nothing guys??

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**Author:** ![NYBo](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/nybo/32/17281_2.png) [@NYBo](https://community.cartalk.com/u/NYBo)\
**Post date:** [June 16, 2008, 8:43pm UTC](https://community.cartalk.com/t/1995-s10-blazer-high-idle-speed-vortec-4-3/15306/5 "2008-06-16T20:43:24Z")

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Try a more thorough cleaning of the IAC and idle passages. Use throttle body cleaner, not WD40. Also check the electrical connector.