i think i had the same problem after switching tbs.it sounds like a loud humm while stopped at traffics lights and while parked and idleing. try adjusting the throttle screw that stops the rotor at idle

 

you still got the stock intake box and baffling/resonators? throw that all back in if its not installed currently.

 

thanks, but I don't think that's the best solution.... i'm sure it would quiet it, but I've got too much tied up into the intake that I'd rather make it work.

 

you speak like you have itb's installed lmfao

 

LOL na... I don't have THAT much money tied up into it, but hell... $200 bucks is $200 bucks!

 

throttle plate sticking open? take the intake pipe off and take a peek, dont even need to turn the engine on to check. only thing i can think of that would "roar" besides an exhaust leak. have you opened the hood to listen or just heard it from inside the car? can you be more descriptive than just "roar"? like is it a roar with a metallic sound, a roar like wind moving very fast, a roar like an openheader v-8? lol roar is very vague

 

it sounds like a vacuum hum... checked for vacuum leaks too, so that's not it. can a dirty IAC cause this?

 

Hi All. I have the same proplem with my D16y8 that Jaybo had back in 2009,just like a vacuum cleaner hum at idle. Have checked all vac. hoses,butterfly plate closes ok,but the noise is driving me nuts. Engine idles perfect & the car goes really well, was wondering if anyone can shine a light on this problem. Mabye a faulty IAC valve or TPswitch??? Thanks John. PS Jaybo,s posts were in D-series Knowledge factory,found by typing in{ D16y8 intake roar }.

 

Check for vacuum leaks.

Start this video at 3:00

 

^^---Beat me to it.

Did you block off the cold air assist whatever thing. The hose nipple in the middle of the intake manifold flange? I've never owned a full y8 so idk if swapping the intake tube will affect that.

But air gets sucked in and flows right above the injectors.

 

Hey Mr. Fodo. Have blocked off every Vac. hose one by one incl. the cold air one but the sound is still there. There is a little about 5/16in round port inside the throttle body just before the throttle plate,looks like it would feed to the TPS and or the IAC valves. The noise is coming from there, so i am waiting for some gaskets & o'rings from Honda so I can check them out. Does any one know if this port leads to any other place. Thanks Guys. John

 

I agree, probably a small vacuum leak.

 

SMH...


How do you think an engine works?

It takes in air, adds fuel, compresses it, then ignites the air fuel mixture and exhausts it, then the whole process starts over.

If the engine isn't taking in air it wont run. If the throttle plate is closed air has to have a way into the engine. Some of the ways is the PCV, idle bypass screw(or throttle stop screw), IACV, and on older cars the FITV(or cold start dash pot).

The very small hole you see at the top of the throttle body just before the plate is the port for the idle set screw, there is also a (or two if there is a FITV) large hole on the left side of the throttle body, this is the IACV port.


The noise is air entering the engine, if you have the stock air intake piping installed the noise wouldn't be heard.

 

Identify the problem, market it to ricers, and profit!

 

Thanks for all the info guys. Gaskets & o'rings arrived today so will start looking tomorrow. Thanks John