loud humming sound

[mediaman67]

Hi All

96 gen 2 4.0L OHV

Im getting a loud humming type sound now when it gets REALLY cold out... it happens at idle mostly, but will eventually stall the engine...

seems like it must be something to do with the intake, since this usually only happens when it's really cold outside. MAP?? or I guess in this MAS?

ideas, thoughts?

I used to get this, but a lot quieter, and it was just that Black cap vibrating on/near the EGR valve... this is a deeper sound, and louder.

I hate the idea of the stalling almost more than the noise, but the noise is annoying too....

Thanks to all

 

[koda2000]

probably the IAC valve

 

[mediaman67]

Hi,

I saw something about the computer having to learn idle trim? - I just installed a new battery, and only have like 5 drive cycles since....

yes, the IAC is where that Cap humm came from before, but this almost seems like it's coming from the air box? but hard to know with the hood down and inside...

Course, I can get it to do this when I have the hood open, and watching the engine idle...

anyone have some advice to see if it's for sure the IAC? I don't want to throw $50 away if that's not my problem....

Thanks

 

[my98nnj]

Plenty of info on here and easy fixes. Search vacuume cleaner noise from engine and you'll get quite a few threads on the topic.

 

[JimMadsen]

Pretty sure you can remove the IAC and still run the engine. You can at least test it this way. Of course your rpm's will go through the roof.

 

[mediaman67]

well, for $40 I just bought a brand new one.... so, we'll see...