Hissing sound

[merle&louise]

I have recently noticed a hissing sound when I accelerate and ascend an incline on a bridge or even on flat ground. If there is a concrete wall (roads under construction) and I push the accelerator to the floor, as the speed increases I hear a loud hissing sound. As soon as release the accelerator, the hissing sound stops!:confused: I can't pinpoint the location of the sound.

Does anybody have a clue? Could it be my muffler? I looked at the muffler and it does need to be changed; it has a few holes in it and is rusting out.

The only air in my system would be in the suspension system; so why would the hissing sound increase when the engine rpms increase?

Maybe the turbo?:confused: The boost gauge pegs out at the max when I push the accelerator to the floor. So I am not losing boost.

Should just buy a new Liberty or try to fix my Newell?:eek:

[m stuller]

Tuga: I have had this happen to me on occasions and found it is coming from the speakers. Once i turn off all the electronics or radio that the sound volume is truned down all the way the sound goes away. Try this as the way you described the hissing sound is exactly the same way that i would describe what was happening to me.

The problem with going out and buying a new coach is that you will have the same problem!

Matt

[Jerry Winchester]

Tuga,

I recently had the same problem and I noticed it because I drove near a barrier like you described with the window open.

Upon further inspection, I had a leak on the pipe that connects the exhaust manifold to the turbocharger. It was the hissing of the leak that caught my attention. An exhaust leak in several parts of the system would sound similar.

Or as Matt stated, I have had many engine / coach problems that turned out to be (A) The girls had a movie turned up too loud in the back (B) The girls had the Nintendo DS cranked up behind me and I couldn't see them (C) The girls had the stereo or some other electronic device running that I couldn't see but could hear (D) My wife was snoring (E) Some moron pulled up next to me in a snapperhead car with a fart can muffler and a 1000 watts of bass.

[merle&louise]

Matt, Thanks for the advice. I checked to see if the surround sound or DVD player was on; all systems off.

JDUB, The exhaust manifold connection to the turbo seems like a pretty good guess. I will begin my search there.

Thanks guys for the quick replies, I'll update as the problem gets closer to being solved.

[JIM CHALOUPKA]

Tuga, My vote is as well for the exhaust. When you are close to the wall you hear the sound upon acceleration and not when backing off. You say you have holes in the ;) system. They leak more under heavy acceleration. Entertainment center sound would not be linked to the throttle.

A periodic drive through areas with walls close by at speed is a good way to notice maintenance items that require closer scrutiny. Sounds that are normally thrown out into environmental space and lost are thrown back at you to be audible red flags!;)

[Jon Wehrenberg]

Tuga,

I don't know how Newell set your exhaust up, but the pipe from our turbo to the muffler has a life of about 10 to 15 years. On our coaches it is especially hard to see all parts of it, but if it or the muffler begins to develop leaks that is what you might hear.

It also might just be the turbocharger and you may have only become aware of it making a noise.

[merle&louise]

Jon,

I have an appointment at Newell for July 23 to have the muffler replaced. I may just wait until that time and road test it after the new muffler is installed to see if the hissing sound still persists. That seems like the best way to attack the problem at this time. I will, however, visually inspect the exhaust manifold connection to the turbo like JDUB suggested.

Jim,

Glad to hear that you concur with Jon on the exhaust being the culprit. Now that I think about it, I remember back when my '93 Newell muffler started rusting out I noticed a pinging sound when accelerating next to a concrete barrier wall.

The more I discuss it, the more convinced I am that the muffler is the problem. Boy am I glad that I don't have to buy a new Liberty!:D

Thanks guys, as usual the POGGERS come thru.

[JIM CHALOUPKA]

Tuga, You don't have to buy a New Liberty! A used one would be just fine.:)

After thinking on your hissing sound, could it be that you used a little Snake Oil the last time you had to add engine oil? :p :D :D

[Larry W]

Just a thought. Before being consumed by MPD I have a similar noise in my glass pusher. Was about to think it would never be found. It was the mic on the backup camera volume control turned way up. Turned it off and no noise.
Larry W
2000 Royale

[rmboies]

Tuga,

When we were caravaning to Kerrville and you and Karen were in front of us, I often heard a roar/hiss noise coming from your coach. It was not constant it would come and go..... Bob told me it was just your jake break but maybe not? If not, then sorry I didn't mention it!! I do like your idea of jumping into a Prevost though, this would be the perfect excuse :p

[truk4u]

Tuga,

Here's a shot in the dark... Does the Newell have an air operated throttle and if so, could it be coming from the pedal.

[merle&louise]

Tom,

I have the same throttle as Roger, which I believe is not air operated but it has a sensor under the accelerator pedal. I used to get an error message "TPS failure low" and I talked to Roger to get a part number from him. I haven't gotten the error message ever since I disconnected the electric connection under the accelerator and plugged it back in. Go figure!

Debi,

I think that you nailed it; the muffler is shot. This would explain why you heard a roaring/hissing sound when we were in front of you and Bob climbing hills on the way to Kerrville.

Is Bob-03 a lucky guy or what; he not only has a beautiful wife, but she is a great diesel mechanic. Some guys have all the luck. Move over Jon!:D


Larry W,

Welecome to the forum, and yes I did think to check the backup camera volume.


Jim,

I'm going to hold off on a Liberty for a while (until Jon puts his up for sale);)

Last oil change I used Diet Coke (it's cheaper than Mobil Delvac 1) instead of Snake Oil. I heard that it is better for a series 60; at least that's what Lew told me.

Thanks for all of the help guys (you too Debi).:D :D

[rmboies]

[
Thanks for all of the help guys (you too Debi).:D :D[/QUOTE]

Glad to be of service Tuga, now where did I put those coveralls??:p

[JIM CHALOUPKA]

[
Thanks for all of the help guys (you too Debi).:D

Glad to be of service Tuga, now where did I put those coveralls??:p[/QUOTE]




Debi, I think Bob 03 said the coveralls are out in the barn (a new never opened package ):D :D

[rmboies]

[QUOTE=JIM CHALOUPKA;
Debi, I think Bob 03 said the coveralls are out in the barn (a new never opened package ):D :D[/QUOTE]


ok, who keeps letting Jim out of his room?? I swear, everytime I lock him in there he comes out to harass me again;)

[JIM CHALOUPKA]

Deb, Only well liked people get teased.:) :D :D

[merle&louise]

Muffler changed; hissing sound is GONE:D

Thanks for all of the advice.

[Danss]

My Generator cranks easy and runs for One minute and ten seconds then shuts down. It will then crank up and do the same thing. Any Ideas? Thanks, Dan

[truk4u]

Danss,

Check your auto-start setting and disable to eliminate that. Also, if you have the programmable quiet time built in to the inverter setup, you may be in the quiet time parameters. I had a CC with Xantrex Inverters and it would do exactly as you said if trying to manually start during the quiet time period.