Well It figured, first nicer day we've had and I let the windows down... sure enough I hear something annoying in the truck.

I am getting a off power hissing noise when cruising... like if I were to slowly let off the throttle at 45. it's very noticible it only happens while I am in gear and running down the road. it only happens when I am on the throttle, but not pushing the truck any faster... more or less while doing a powered coast. I have checked all my vacume lines and cant find any craks. I'll do a good test on them tomorrow when I stop by dads.

could this be one of those dreaded plenum problems???

 

pickup a hand operated vacuum pump, and see if you have any leaks, if you do then just inspect everyhose and line until you find the right one. It sounds to me like it could be where the aircleaner attaches to the throttle body, but then it would do it in park, check it also

 

yep dad will have a pump, so when I swing by there I'll borrow it for a little bit.

thanks for the tip on the air cleaner, I'll give it a good once over then too.

 

its just throttle body hiss. If you have anything besides the stock intake it will be louder than normal as well

 

I put a 14 round and notice a hissing, everyone telling me that is normal, it is loud but I am getting use to it.

 

I gots me a bad o-ring? or whatever you wana call it where the air cleaner connects to the thingy.. mine likes to hissss, needs to get me a new oring thingamabob

 

Timsalas i think we have the same problem... I had a few suspect vacume hoses so I swapped em out while I was under the hood... believe it or not made the hissing louder. it's not a big thing but it is annoying.

 

mine does the same thing i gotta K&N air filter and it got twice as loud i kinda like it lol sounds mean haha!

 

Anybody figure this out. It is happening to my 97 Ram. As soon as I let off the throttle, I get a hiss inside the cab. It sounds like letting the air out a balloon, slowly.

 

If its not a vacuum leak, and the seal between the TB and air cleaner are fine, its either the 14x3 air intake or the CAI intake, I bet you. Both my wife's CAI K&N and my 1995 Dakota with the 14x2.5 K&N that I used to have did it. Perfectly normal.

My two cents.