noise on acceleration, sounds like a miss but engine feels good and no check engine light, eventually goes away, not there under a load either, idk totally stumped

 

You don't say what engine you have, but I'm going to assume the V-10.
Take a look around your exhaust manifolds, check to see if you have any broken/missing studs/bolts, don't panic they are a common issue on these motors. A broken stud can lead to an exhaust leak that may be giving you that sound, there may be signs of soot buildup around the head to manifold mating joint. Dealing with broken studs can be a real hoot , look in the Tech Folder at the top of this forum for a couple of threads on manifold stud removal and header installation.
Another strange noise on these motors is a metalic vibrating sound while accelerating around 1800-2200 RPMs, this is from the sheet metal cover on the bottom of the the torque converter, it can be removed to check if it is the noise maker and a little bending and retightening should quiet it down when you put it back on.

 

hey thank you for the reply I'm gonna check it out today

 

Most of the Excursions aren't OBDII compliant, and these models will not set the CEL for a misfire code. My X had two misfire codes present when this happened, yet the light never turned on. Needs to be scanned anyway.

 

Yep. Just last week I decided to scan my truck and discovered two misfire codes. Like Tom said, they do not trip the CEL.

 

its funny the truck can idle and if i rev it up nothing its only when you accelerate id drive

 

and i just checked no codes came up either

 

i do have one broken stud on the drivers side exhaust manifold but no balck spots or soot around it so idk still stumped, i was told too that the boots on the plugs go bad and it could be a jumping spark too ?

 

It's possible, but more likely you would have a misfire code if that were happening. I'm guessing it's a misfire that's not consistent enough to set a code.

You could try changing out your plug boots and checking the plugs.

 

You don't have new ones in there but you are asking about a miss?

 

honestly it sounds like a miss , it happens upon acceleration but eventually goes away, under a load to its not there so idk really