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Discussion Starter #1
So, in my recent barrage of problems on my truck, the truck just all of a sudden started to idol really rouge in the mornings when I would start it up, so I would have to hold the gas down at 2000 rpm for about a minutes to make it go away, after that, it would keep idling without dying.

Now, I just replaced the cap and rotor, and the truck dies pretty much instantly on start up when it hasn't run for a while. So I hold the gas down while starting it up and hold it for a minute or so and it'll keep idling, roughly, but it keeps going.

On the road, I don't have any problems with it, gets great power, no misses or anything, just when sitting idol it starts to have issues. I suspect the Idol Air control Valve is either dirty or is going bad...is there a way to clean this, seeing as that I can't get a new one for a while cause they are $40. Or could it be something else?
 

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Discussion Starter #2
Ok, so I replaced the IACV and it fixed the rough idol problem, but not the start up problem. It still dies instantly on start up unless you give it a little bit of gas when starting it. I'm out of ideas, any help?
 

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Try cleaning the throttlebody with throttlebody cleaner. Take the new IAC out and spray the area were the IAC goes in. Its best to take the t/body off so you can clean both sides. Use a soft toothbrush and t/body cleaner, don't use carb cleaner. I like CRC brand t/body cleaner. If a throttlebody is gummed-up it can effect idle. The have bypass ports inside that help with idle and if they get plugged up it will effect the idle.
 

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Discussion Starter #4
Well, I did spay a bunch of carb cleaner in the IAC port before I put the new one on, and a bunch of grim and stuff came out. And it idols fine since I replaced it, it's just the truck wont start now unless you push on the throttle a bit while turning it over, then it will idol really really low, like 400-500 rpms.

I'll try taking the TBI off and cleaning it, the PCV port looked a little bit nasty when I had it off.
 

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As I said in my other post, DON'T USE CARB CLEANER. The throttlebody blades have a clear coating from the factory and some/most carb cleaners can remove this coating.
 

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Also won't hurt to check your timing...

Just be sure to disconnect the PCM connection first.
 

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Discussion Starter #7
Ok, so I went and bought some throttle body cleaner, and cleaned the crap out of the TBI, sprayed it in all the ports, the EGR port, the PCV port, and all the nooks and crannys and put it all back together, and it fired right up. All it needed was to be cleaned, wonderful how it's always the simple things.
 

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Glad to here that was the fix.

---------- Post added at 10:14 PM ---------- Previous post was at 10:12 PM ----------

Glad to hear that was the fix.
 
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