I bought my 4.7L V8 2007 Dak in 12/08 and it has never idle like that!!

 

most of us that had issues got the wrong plugs from the dealer, i pulled my plugs and 4 were the correct plug, 4 were different plugs, the plug gaps were all over the place, get a set of autolite 3923 plugs, copper core, not plats and gap them to 40, see if the truck idles better, guarenteed the gaps and plugs in the truck are wrong, walmart under 20.00 for 8 plugs

 

My '05 4.7l idled a little rough before the battery went dead. I took the battery cables off while going to get a new battery so the PCM had time to reset. When I drove it with the new battery, it ran MUCH better, idled smoother and felt more powerful. It might be the full battery voltage or maybe the PSM reset or both. I ues Iridium plugs and am happy with them.

 

Hey guys, I got a 2005 4.7, never really had any idle problems until recently. Funny thing is, it started right after I added a cat back magnaflow, AFE dry filter, plus I flushed my tranny and rear dif, finished up with a fuel system cleaning. My first thought is it may be my spark plugs. I am gonna replace them with the copper core ones that everyone keeps reccomending. Let you know if it makes a difference. On a side note, in addition to the rough idle, I noticed that my truck now is making a wierd sound. I can only describe it as a mid-high pitch whirring sound that picks up when I accelerate and seems to "wind down" when I let off the gas. I'm concerned that something may have gotten messed up when I flushed my tranny and rear dif. Got any idea's?

 

I second this, mine used to shake some at idle till I switched in the 3923's. My plug gaps from the factory were all over the place too, they must have been drunk when they gapped them.

 

Whats the plug gap for the 3.7? Are the plugs on the 3.7 easy to change?

 

iam currently having a rough idle issue. i swapped to the autolite 3923's and havent noticed a difference. i noticed the gaps were all over the place on the ones i removed. some at like .50, .55 i gapped all the autolites to .40 and still hasnt fixecd the rough idle issue. dont know what else to try out

 

i live with it because from what I've read on here, some people have luck doing one thing, others throw money at it left and right and it never goes away. The ONLY time my shaking at idle went away was when my battery was disconnected overnight. That was about 5 months ago and the shake is back, so I guess it's time to disconnect the battery again, but really it's just not that big of a deal to me.

 

yeah it'll do that with a newer filter like KN or w/e it'll make a little more hissing sound or if you put a CAI on it OMG you'll hear it...no worries just the intake!