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Discussion Starter #1
so i was sitting im my driveway tonite letting my turbo cool down and was staring at the tach...it will idle at 900 and the needle will bounce between 850 and 900...then the engine sounds like it gets a slight load put on it and the needle will quit wiggling...is this normal? i have only had the truck a few days so i dont know much about it yet...thanks
 

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Future Fly Boy!
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id say that is about normal...i think mine idles around the 800 mark...and it will bounce...i have the rpm set to show on my edge display and that number never stays still...always changing...i think your truck is doing just fine:thumbsup:
 

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Did you have the a/c or the defroster on? This will make your a/c compressor cycle off and on and will make the motor rpms change slightly. Also would cause the load you were hearing with the motor? I would say nothing to worry about at this time!!:thumbsup:
 

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My idle moves around when the heater grids cycle which is normal. Its a 190AMP draw on the electrical system.
 

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mine does the same thing...and it is much more pronounced when the defrost is on, but still rather noticable when its not on too.
 

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Rescue Tower
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mine does the same thing...and it is much more pronounced when the defrost is on, but still rather noticable when its not on too.
Ummm... that runs your AC like scooter said.
 

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yea thats normal, i got the same thing.. whether or not your a/c's on, the "condenser" i think it is, still kicks on for a few seconds every 30 sec or so.
 

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Discussion Starter #8
cool beans:thumbsup: thanks guys!
 

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Iv kinda had the same problem, mine just i can start it up in the mornings and it idles smooth, drive it for a little while at 60 to 70, and i wait for the turbo to cool off and has kind of a rough idle to it. What do yall think it is?
 

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Yes, the compressor will kick on when your defrost is on. It removes the moisture from the air so the windshield won't fog up.
 

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On call 24/7
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Mines moves slightly too. I always though mine idled high, closer to 900 but if you actually count the marks between 0 and 1000 rpm you will only count 9 marks so Im not sure if its 8 or 900 but all the 2nd gens Ive been in are about the same.
 

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mine does the same thing when no ac or anything is on also fuel pressure drops about 2 psi what the heck causes this?
 

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My tack shows 900ish cold. 800ish warm in park. in gear around 800ish
Now if yah check the edge tach it's closer to 850cold 800warm and in gear 750(digital gauge moves +-5 but the dash is much more voilite. Hope this helps a little.
 

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Rescue Tower
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mine does the same thing when no ac or anything is on also fuel pressure drops about 2 psi what the heck causes this?
You have something else going on. Check voltage levels to your pump when this occurs. Are you using a relay to run your pump?
 

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cumminsforum.com
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mine does the same thing when no ac or anything is on also fuel pressure drops about 2 psi what the heck causes this?
The only thing that can do that is grid heaters but that at the first start up of the day...:confused013:

Funny part is I use to see that kind of drop with my Carter pumps all the time now with the AirDog 150 I don't...:confused013:
 
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