Odd new sound at shutdown

[Randy Van]

It was time for an air filter replacement, so I figured while I was at it I would remove the air intake silencer, and try a K&N drop in.

All went well, however I notice now when turning the engine off there is an odd new sound that was not present in the past. Sounds like a tennis ball being dropped into a plastic pail.

If you turn the key to the on position within 15 to 20 seconds after the engine has been shutdown, the same Odd sound is again heard.

The sound is originating from the throttle body/intake area.

Is there a vacuum controlled valve under the throttle body cover capable of making this odd sound? :unsure:

The truck seems to be running fine...

 

[EddieS'04]

It is the IAC opening and closing. The paper filter and the silencer dampened the sound as where you never heard it before.

 

[Randy Van]

Thanks for the reply Fast Eddie.

I was thinking the same thing and back tracked as far as putting the silencer back into the air box... but I had already tossed out the old paper filter, did not notice a big difference.



I do find it strange however that I was not able to to find a similar post.

With the number of airbox mods and cold air intake installs one would think it may have been mentioned... will look at cleaning IAC project, couldn't hurt

 

[Randy Van]

Yes, it has been mentioned, in a similar post ... look what I found !