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Whining sound and jumpy accelerating.
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Author:  allworthy [ Tue Feb 22, 2011 8:39 pm ]
Post subject:  Whining sound and jumpy accelerating.

Hi, might anyone have any suggestions to why I can hear a whining / whirring sound with my 944 when I accelerate. Its most apparent when im cruising in 5th gear, the more I push the pedal the louder it gets, and when I take my foot off it the sound goes. Also its a bit jumpy at accelerating, especially in 3rd gear. If I stop pushing the pedal and cruise, I have to press it very gently when I speed back up otherwise it jumps and wont speed up smoothly. Could this be a problem with my fuel pump as the problems only happening when im accelerating. Any suggestions welcome.

Author:  Oct [ Wed Feb 23, 2011 1:11 pm ]
Post subject:  Re: Whining sound and jumpy accelerating.

Whining sound may be the diff.Changing the oil in it should make it less noisy.

Author:  J.J. [ Wed Feb 23, 2011 9:01 pm ]
Post subject:  Re: Whining sound and jumpy accelerating.

Sounds like the diff' & they all do it. If you can still hear it with the window open then the bearings are getting tired. But as said changing the oil can help. You don't need Swepco. Just a modern semi synthetic will do the job. Jumpy accelerator could be a lot of things but check the linkage & condition of the Air flow meter. & throttle position switch for starters.

Author:  lindsayhbrown [ Wed Feb 23, 2011 9:34 pm ]
Post subject:  Re: Whining sound and jumpy accelerating.

Whining could be belts too tight if coming from the engine and increases with engine revs

Author:  Richclarkes2 [ Thu Feb 24, 2011 11:41 pm ]
Post subject:  Re: Whining sound and jumpy accelerating.

What i get with my diff (which is noisy) is more apparent when crusing at around 70 is the constant whine note of the diff and the note of the engine almost matching but just off so the two notes together go out of phase creating a modulating sound, it makes it sound like the exhaust note is going wom, wom, wom, like a wheel bearing noise, when really its not.
Sound familiar?
Rich

Author:  Chris924 [ Thu Feb 24, 2011 11:53 pm ]
Post subject:  Re: Whining sound and jumpy accelerating.

You only hear the whining diff because you don't have whining kids in the back like most cars!

Turn up radio 4! :lol: :lol:

Author:  J.J. [ Fri Feb 25, 2011 12:41 pm ]
Post subject:  Re: Whining sound and jumpy accelerating.

lindsayhbrown wrote:
Whining could be belts too tight if coming from the engine and increases with engine revs


If belts it does it all the time. Even at idle. Only the diff' does it when power applied & then goes quiet when you lift.

Author:  Richclarkes2 [ Fri Feb 25, 2011 1:04 pm ]
Post subject:  Re: Whining sound and jumpy accelerating.

My diff noise is constant with road (not engine) speed, power applied or not and with clutch dipped.

Author:  allworthy [ Fri Feb 25, 2011 8:10 pm ]
Post subject:  Re: Whining sound and jumpy accelerating.

Right o, i'll try changing the oil. Never done that before, just read up on it though and it sounds simple enough though. Should I drain all the old oil out first or just see if it needs topping up? Also will I be able to squeeze under without any jack stands? Im pretty slim but the cars pretty low...

Author:  951jamie [ Fri Feb 25, 2011 8:52 pm ]
Post subject:  Re: Whining sound and jumpy accelerating.

Drain all of it ! Be careful the fill and drain plugs are very thin walled!! Also the whinning could be the torque tube bearings!

Author:  fullchat [ Fri Feb 25, 2011 8:58 pm ]
Post subject:  Re: Whining sound and jumpy accelerating.

OK, I'll say it before anyone else!!

Before you undo the drain plug and drain all the oil out, make sure that you can get the filler plug undone, otherwise you will have an empty gearbox with no way of refilling it :(

Author:  allworthy [ Mon Feb 28, 2011 10:04 am ]
Post subject:  Re: Whining sound and jumpy accelerating.

The haynes manual says I need SAE 90W gear oil, will any oil of this type do or is can anyone recomend one? And how much will I need to fill it after I drain all the old stuff off?

Author:  Oct [ Mon Feb 28, 2011 1:09 pm ]
Post subject:  Re: Whining sound and jumpy accelerating.

Image

Author:  951jamie [ Mon Feb 28, 2011 5:34 pm ]
Post subject:  Re: Whining sound and jumpy accelerating.

Any 75W-90 gear oil should be fine.

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