GM 4.3 V6 Low Idle Speed Increase

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Staff member
Dec 14, 2002
New Jersey
Hello, My 98 S10 has always run great. Strong and powerful, reliable, and off-idle, pretty darn quiet and smooth. But idle is off. It shakes, but the key thing is that it only idles at 500 RPM. Too low. It has never thrown a code. I cleaned the EGR and ICV, showing some of that here: And I think another thread. So since I have no codes, no vac leaks that I can tell or find, and the engine runs great, how do I perfect it by getting my idle speed right? Thanks!
Per the other linked thread, Ive cleaned the TB before, which wa spotless before I cleaner it and moreso after. The TB is clean. This has not helped me in the past, and so I don't count on it to fix it now.
4.3 Really? I was under the impression that it was more like 650 or 750. Ive owned the truck since new but honestly cant remember what it did new. The rest of the truck is like day 1, so if I just fix this (and the shake that wasnt there when new), then all will be GREAT. Thanks!
i have a 91 c-1500 4.3L and when the idle was off i checked the timing and it was way off! i fixed the timing and idle was back to normal. this might not apply to your obd II 4.3l but it is something to check into (timing chain slop etc...). but i agree check the throttle body first. mike
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