Strange sound with cruise control

[JSanchez]

Hello all,

I posted the following in the wrong section by mistake:



"Hello all,

I heard a strange sound while engaging the cruise today. It is something like an "rrrrrrrrrrr" sound coming from the engine compartment (vacuum pump?), and did it when I'd first engage the cruise, and intermittently while it was on. I've never noticed it before, but it was very quiet this morning going through a tunnel.



I am wondering if anyone can tell me what this sound might be and why. Is it normal? I'd appreciate any feedback.



Thanks,

J. S. "





Thanks again fellas, and my apologies for double posting.

-J. S.

 

[AH64ID]

Look on the back side of your passenger battery, if there is a vacc pump there it may be going out or its normal and just never heard it before.

 

[JSanchez]

Thanks for the reply. I'll have a look, but does anyone know if the vacuum pump usually makes this type of sound, or is it only when it is having a problem of some sort?

-J. S.

 

[roadking]

We don't have vaccum pump's on 03 and up trucks

 

[rscurtis]

If it's an automatic and has cruise control, it has a vacuum pump.

 

[Bill Stockard]

We don't have vaccum pump's on 03 and up trucks

The '03 trucks don't have a mechanical vacuum pump like found on first and second generation trucks. However, there is an electric vacuum pump on '03 trucks with an automatic transmission and cruise control. It's used to operate the cruise control servo located under the driver side battery. The electric vacuum pump is located on the fender well behind the battery near the firewall on the passenger side and it does make a noise when it's operating. I hear it running when turning on the key before starting the engine, but don't hear it when driving. A failing vacuum pump may make more noise.



Bill

 

[roadking]

The '03 trucks don't have a mechanical vacuum pump like found on first and second generation trucks. However, there is an electric vacuum pump on '03 trucks with an automatic transmission and cruise control. It's used to operate the cruise control servo located under the driver side battery. The electric vacuum pump is located on the fender well behind the battery near the firewall on the passenger side and it does make a noise when it's operating. I hear it running when turning on the key before starting the engine, but don't hear it when driving. A failing vacuum pump may make more noise.



Bill

I stand corrected, i don't have one.

 

[Bill Stockard]

I stand corrected, i don't have one.

Don't feel too bad. When I first purchased my '03, I mistakenly thought the electric vacuum pump also operated the doors on the HVAC system. I was corrected by a post on this forum.



Bill