I own a 01 screw 5.4L 4x4 with about 62K on it. I've changed the plugs and COP (all of them) and it runs fine, no stumbles or anything like that. But the vehicle has always had a little "Delay" in response from the time I give it gas to acceleration and when I mean little I mean just enough to know its there. The vehicle runs great at speeds slow and fast, no bucking or jerking. At idle it’s so silent at times think its cut out, but is just very quiet. Today I had a little time so I popped the hood and had the engine running and started to manually accelerate it using the throttle linkage and notice that as I gassed it there was this sound of rushing air right before the engine revved up. Just like the delay I was experiencing. So I did it several times and sure enough as it gassed the engine right before the engine revs up there was the air rushing sound around the TB area. My question is: is this air rushing sound normal? I've never cleaned the TB or MAF, but I can’t figure out what this air rushing sound is right before the engine revs up? Anyone have any ideal what this is? I'm sure suspecting this is what's causing this acceleration delay? But then again I'm no expert.

 

I think you should take it and get it checked out........













































lol, thats normal, that is just the vaccuum from the engine which draws the air in.

 

I have a 2001 5.4 supercrew with 98k miles on it. My truck does the same thing. It's normal.