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2004 chevy trailblazer_ls
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Discussion Starter · #1 ·
I've had my tb for like 3 months. Recently i started to notice that when i have it just running at idle in park position, it idles at about 600 rpms. But about every 3-4 minutes, the engine almost dies, dropping below 500rpms. Then it catches and returns to about 600. I have no idea what could be the cause. Any suggestions please!
 

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2004 chevy trailblazer_ls
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Discussion Starter · #5 ·
so i completely cleaned the throttle body.

Now the engine no longer drops idle and almost dies, so thats a plus, but now it will jump up to 1k and back down to 600 rpm. I'll take that over the other. Any ideas on why it won't just stay constant
 

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2003 chevy trailblazer_lt
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it will stop doing it just give it a little time. if you disconnect the battery the pcm resets and now has to adjust it self
 

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2004 gmc
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Was it icky before you cleaned it? How many miles?

The PCM has some adaptive programming, so it got used to the disability the old TB gave it. Now it has to learn how to walk all over again. GOod news it's a quick learner and might only take an hour of driving with varied conditions. (Freeway driving doesn't force it to learn very quickly, since it's boring.)
 

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Discussion Starter · #9 ·
Great Fix!

So i unhooked the battery last night for over 30 minutes as some people on here recommended to clear the vehicles bad habits with the dirty throttle body. When I went to work, i reconnected it and let me tell you, it drives like a whole new tb. The erratic idle is gone, its smooth and steady and the acceleration is much more responsive.
 

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Discussion Starter · #11 ·
i would assume so:undecided. There are people on here better at answering that then myself. I bet it's exactly the same since it uses the same technology in just a bigger setup.
 

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Northwest Chapter
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Does the same issue apply to the v8? having a similar issue...

Thanks

Steve
Not nearly as much Steve, the reason the I6s are so sensative to the throttle body being clean is that they do not have a PCV valve and the EVAP canister purges through the throttle body. If the EVAP canister is purging and you close the throttle, bam the EVAP gases fly to the backside of the throttle plate.

Its worth a shot for sure, no one has posted up a how to for the V8s because its not done nearly as often but go for it.

And disconnect the battery BEFORE you start messing with the throttle body, that way you cant screw the electronics up and you're guaranteed to have the PCM reset itself.
 
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