[boophoenix]

Just out of curiousaty what is this notorious bumble bee? It will just out of no where make a buzzing sound may only be once or many times. There doesn't seem to be any pattern to it. My truck can set for a week and I can go out to get into it and low and behold the bumble bee is there. It even did it the other day with the battery terminals removed. The best I can tell it is coming from here ( see attached photo ). I've only ever heard this sound from my truck and a gmc topkick.

96 ext 4x4 2.7L

 

[atwinda]

I am pretty sure that's the brake booster... No idea why it makes a noise..

 

[sjvicker]

I would also like to know more detail about this one.

 

[boophoenix]

I am pretty sure that's the brake booster... No idea why it makes a noise..

I think you're warm. The break booster is in that area, but it's the round critter on the firewall behind the the master cylinder. I'm thinking vacume canister maybe, but never knew the purpose os these critters.

I have no clue about the noise either. I've thought about shooting it a few times to put it out of it's missery though. It sounds as if it's suffering so bad, lol!!

 

[boophoenix]

I would also like to know more detail about this one.

Is yours suffering terribly as well?

 

[joeylead]

Just out of curiousaty what is this notorious bumble bee? It will just out of no where make a buzzing sound may only be once or many times. There doesn't seem to be any pattern to it. My truck can set for a week and I can go out to get into it and low and behold the bumble bee is there. It even did it the other day with the battery terminals removed. The best I can tell it is coming from here ( see attached photo ). I've only ever heard this sound from my truck and a gmc topkick.

96 ext 4x4 2.7L

Do you have ADD? I am almost positive that is the vacuum actuator for the front diff. See if the hoses go down to the diff. If they are byssing, perhaps one of thehoses has a leak?

 

[boophoenix]

Do you have ADD? I am almost positive that is the vacuum actuator for the front diff. See if the hoses go down to the diff. If they are byssing, perhaps one of thehoses has a leak?

I do not think I have an ADD. Just to be sure I did a quick crawl under in the rain a few minutes ago and I beleive the acuator for this setup would be on the passenger side of the dif and I have no such critter there either.

The one hose that goes down from this thing apears to end in the frame rail just below the upper arm mounting points. It seems I read something in the old board about this ( the line going into the frame that is ).

From front to rear of this component it apears the hoses are
1: hose to frame
2: hose to breather lid
3: ( small line ) to sensor of some sort
4: around by the firewall threw one or two sensors then to the top of the throttle body

 

[SilverTaco]

Do you have automatic hubs or do you have to get out and lock them?

 

[Ohio_Taco]

I have the same sound coming from the same place on my 4cyl. It has been making the noise for over two years. I kind of just ignored it but would like to fix this problem

 

[boophoenix]

Do you have automatic hubs or do you have to get out and lock them?

I have lockout hubs. I looked under just to be sure there hadn't been any conversion with left over parts.

 

[96tacolx]

Is it a constant buzz or does it stop for a couple of minutes and then buzz again? On mine with the engine off I hear a short buzz (like bumblebee) and then a couple of minutes will pass and then a short buzz again. This will continue for a long time and I just contributed it to the truck being run. I don`t think it does it if the truck hasn`t been run a day or two.

 

[John Luttrell]

That is the evap canister for the fuel vapor evap system. It was kind of common for the check valve inside the canister to vibrate on this model trucks as fuel vapors were ported into the purge canister. When it is buzzing, you can remove the fuel cap far a few seconds and the buzzing will stop. It causes no harm to anything, but can sure make you go................hmmmmmmm.

 

[boophoenix]

Is it a constant buzz or does it stop for a couple of minutes and then buzz again? On mine with the engine off I hear a short buzz (like bumblebee) and then a couple of minutes will pass and then a short buzz again. This will continue for a long time and I just contributed it to the truck being run. I don`t think it does it if the truck hasn`t been run a day or two.

Mine seems to do it for up to a week of sitting in the yard.

 

[boophoenix]

That is the evap canister for the fuel vapor evap system. It was kind of common for the check valve inside the canister to vibrate on this model trucks as fuel vapors were ported into the purge canister. When it is buzzing, you can remove the fuel cap far a few seconds and the buzzing will stop. It causes no harm to anything, but can sure make you go................hmmmmmmm.

Thanks that sounds like a good starting point. Any idea if there is a cure other than total replacement or removal? What would be the effects of removal?

 

[John Luttrell]

I don't think the purge valve can be changed out seperatly, you would have to change out the whole purge canister, which might be costly. If you remove it, you will not pass smog testing and it's illegal................but I didn't see anything.

 

[CMB1998]

Is yours suffering terribly as well?

Its the vacume canister for the EFI.

Chris