Does anyone have this noise?

AZ-Z71 · June 10, 2004

Driving along.

You put the pedal down and the truck starts to accelerate.

You pick up speed but then you start to hear this noise.

Kind of hard to describe, maybe like a vacuum leak on the drivers side. Definately not an exhaust tic or exhaust leak.

When you let off on the accelerator it appears to go away but maybe it is just quiter, at any rate I don't hear it. Regular driving you don't hear it, only when you get on it.

No stored codes or flashing SES.

Tried to narrow it down. It seems to have a slight performance decrease but the truck will continue to accelerate.

I think it happens more when the A/C is on but not 100% sure.

Anybody??

ToeJam · June 10, 2004

Sometimes I can hear what sounds like a whistle coming from the intake. The sound is related to the throttle and is more noticable when I'm going up hills. Could this be what you're hearing?

AZ-Z71 · June 10, 2004

No it doesn't really sound like a whistle. More of a slight hiss and more from the area around the firewall but lower than the Master brake cylinder.

99Silver6.0 · June 11, 2004

I had some funky noises coming from under my dash while back. I stuffed some foam into the sleeve the steering shaft goes through and it helped alot. Maybe give that a try.

Sierra04SLE · June 11, 2004

It may be the brake boost accumulator, they can sometimes be heard

asilverblazer · June 11, 2004

I think the noise that you describe is the same as one that my truck makes. I thought it was just the motor showing signs of its mileage. (100,000)

AZ-Z71 · June 12, 2004

Maybe so I'm at 107,000!

Also not connected to the first noise, or at least I don't think, does yours hiss for a few seconds after shutting it down.

ArizonaSilverado · August 3, 2004

Driving along.

You put the pedal down and the truck starts to accelerate.

You pick up speed but then you start to hear this noise.

Kind of hard to describe, maybe like a vacuum leak on the drivers side. Definately not an exhaust tic or exhaust leak.

When you let off on the accelerator it appears to go away but maybe it is just quiter, at any rate I don't hear it. Regular driving you don't hear it, only when you get on it.

No stored codes or flashing SES.

Tried to narrow it down. It seems to have a slight performance decrease but the truck will continue to accelerate.

I think it happens more when the A/C is on but not 100% sure.

Anybody??

I have the same noise. For me, when I drive around 65 and above the noise is constant when I am lightly on the throttle. I have had it in the shop for this several times. First they claim the noise isn't there, then they claim it is there and it is "Operatiting as designed". They said it is the Throttle by wire mechanism and the noise is coming from the throttle body. I had an 02 silverado which never made such noise (02's didn't use throttle by wire, it had a cable). We also have a 03 Yukon that does not make this noise. I am soooo frustraited by this noise and the lack of the dealer fixing it that I am ready to huck the GM and go buy a F#rd! I honestly can't stand to drive the truck on the highway because of this noise.

jhm · August 3, 2004

I have had the same noise in the past. The dealer traced it down to a vibrating 4wd shift selector mechanism. They replaced it and it went away. I also noticed it was much more noticeable with the air on. Probably due to the extra load on the engine/drivetrain. If you have a 4wd, try holding the shift selector while accelerating, in my case the noise would go away which is how they figured it out.

muddog · August 3, 2004

Im not sure if it is the same noise that you hear, but when I get on the gas I sometimes hear a "sucking" sound. To me it almost sounds like something trying to suck oil....but I dont think thats what it is, just the only way I can describe it....

AZ-Z71 · August 3, 2004

What it feels like if there was some sort of limiter on it that is governing the power. The rpm's are high but not near the 5600 max limit. The speed is well below the 96 mph cut off.

Basically it is like you jump on it and start to wind the truck out then you here the noise and it is like the truck just doesn't have any more to give. It seems to be worse with the A/C on. Also noticed it is outside temp sensitive, the warmer it is the more often heard. On a nice cool morning in the 80's I don't usually hear it.

You will definately hear the noise on a warm day trying to pull the hill between Phoenix and Payson if you jump on it.

The noise is also not the fan clutch.

Really hard to describe, maybe like a high speed sputtering.

What I have done:

Pulled the plugs at approx. 90,000 - they looked like they were brand new, re-gapped them, actually they were under gapped, put them back in.

Thinking about changing the wires but not sure if that will help.

How about torque converter or something? Maybe when I get on it and it down shifts into the next gear and the rpms come up , it winds out the gear but because I'm on it it does not shift out???