New engine whine noise

GerryT · 1st August 2008, 22:32

I don't know how to properly describe it , but if i rev my engine i am getting this noise that i would say is an alternator whine that i can here above the engine.

Its not there if i rev it from under the bonnet but in normal driving its there and it is ****** getting to me.

So have i got a cat stuck on one of the belt's or is it something worse? , i don't have any warning lights on the dash and it runs fine, charges and all its just that blooming noise

Any idea's, is it the alternator or is it more sinister than that ???

David3807 · 1st August 2008, 22:37

Do you still get the noise with the A/c switched off or on econ ??

GerryT · 1st August 2008, 22:45

Quote:

Originally Posted by David3807

Do you still get the noise with the A/c switched off or on econ ??

Yes David its there at all times, the A/C is fine and cold, i must admit to never using econ as of yet , its like a sort of "yeeeewaaaa" noise as i am going though the gears if that makes sense

David3807 · 1st August 2008, 23:04

Well it was just a thought. I have a whine type noise which rises and falls with engine revs, more so in lower gears , which seems to disappear once in top. Probably other noises drowning it out.

Dont get the noise when the Ac is off or in econ mod ie when Ac compressor is not in use. Never have got to the bottom of it but it hasnt got worse in 30k miles.

A few others seem to have noticed the same thing cos there was a recent thread - about two/three weeks ago.

Mines an Auto 75 2.5 but also had similar on previous Auto 75 2ltr (V6)

Dave Goody · 2nd August 2008, 19:20

Quote:

Originally Posted by GerryT

I don't know how to properly describe it , but if i rev my engine i am getting this noise that i would say is an alternator whine that i can here above the engine.

Its not there if i rev it from under the bonnet but in normal driving its there and it is ****** getting to me.

So have i got a cat stuck on one of the belt's or is it something worse? , i don't have any warning lights on the dash and it runs fine, charges and all its just that blooming noise

Any idea's, is it the alternator or is it more sinister than that ???

You haven't had a new Catalytic convertor fitted have you? These can make a noise like this especially if you buy a cheap one like I did? Dave

GerryT · 2nd August 2008, 20:38

Quote:

Originally Posted by Dave Goody

You haven't had a new Catalytic converter fitted have you? These can make a noise like this especially if you buy a cheap one like I did? Dave

No Dave, but i ain't had her long,so i don't know what has been done to her, all i can say is its a new noise that in the lower gears sounds like a BMW Mini supercharger, ie very much a whine, i was even going to attack the air filter box with a screwdriver last night in an attempt to drown out the noise with more of an induction type rumble , then i put the beer away

Simon · 2nd August 2008, 21:52

Induction-type rumbles do not hide the noise... Trust me

Like David describes above, there is a whine when the A/C compressor is in use - especially noticeable when the engine is cold. I also have whining noises associated with the power steering pump.

Around 2200-2400rpm there is a pronounced resonant whine from the engine whilst under partial or full throttle - but this is just resonance from the air in the manifold and I don't think it's anything to worry about.

Tyler Durden · 2nd August 2008, 22:14

Damaged gearbox? Just thinking, if its not whining when you rev it static.

Also, is it deffo not coming through the speakers (can do even when power off). worth another listen, a dodgy earth can cause this.

Hope you get it sorted soon

GerryT · 3rd August 2008, 16:47

Quote:

Originally Posted by Simon

I

Around 2200-2400rpm there is a pronounced resonant whine from the engine whilst under partial or full throttle - but this is just resonance from the air in the manifold and I don't think it's anything to worry about.

That sound like the culprit , i have next week of work, i might just pull out my adjustable spanner, my screwdriver and the universal adjuster , don't worry these were all bought from my local filling station and are top notch tools and having costing me £1.99 with several gallons of fuel i would say a bargain

GerryT · 3rd August 2008, 17:01

Quote:

Originally Posted by Tyler Durden

Damaged gearbox? Just thinking, if its not whining when you rev it static.

I dont think it is m8,least i hope it aint. Its coming from the engine , one thing i did notice today was with the engine running and you rev it from under the bonnet it does seam to suck air from under the engine cover, i will get the cover off this week and have a further look.

1st August 2008, 22:32	#1
GerryT Avid contributor MG ZT+190 Join Date: Jun 2008 Location: Birmingham Posts: 204 Thanks: 0 Thanked 0 Times in 0 Posts	New engine whine noise I don't know how to properly describe it , but if i rev my engine i am getting this noise that i would say is an alternator whine that i can here above the engine. Its not there if i rev it from under the bonnet but in normal driving its there and it is ****** getting to me. So have i got a cat stuck on one of the belt's or is it something worse? , i don't have any warning lights on the dash and it runs fine, charges and all its just that blooming noise Any idea's, is it the alternator or is it more sinister than that ??? __________________ [SIGPIC]http://www.the75andztclub.co.uk/foru...ine=1215021130[/SIGPIC]

2nd August 2008, 22:14	#8
Tyler Durden Avid contributor MG ZT CDTi 135+ Join Date: Jul 2008 Location: Suffolk Posts: 161 Thanks: 0 Thanked 0 Times in 0 Posts	Damaged gearbox? Just thinking, if its not whining when you rev it static. Also, is it deffo not coming through the speakers (can do even when power off). worth another listen, a dodgy earth can cause this. Hope you get it sorted soon __________________ "Sometimes you're the pigeon, other times you're the statue" Last edited by JohnDotCom; 3rd August 2008 at 18:12.. Reason: Bypassing Swear Filter

1st August 2008, 22:37	#2
David3807 Posted a thing or two 2002 R75 Conn SE 2.5l Auto Tourer, 2001 R75 Conn SE 2.5 Auto Saloon Join Date: Nov 2006 Location: Gravesend Posts: 1,897 Thanks: 0 Thanked 2 Times in 2 Posts	Do you still get the noise with the A/c switched off or on econ ??

1st August 2008, 23:04	#4
David3807 Posted a thing or two 2002 R75 Conn SE 2.5l Auto Tourer, 2001 R75 Conn SE 2.5 Auto Saloon Join Date: Nov 2006 Location: Gravesend Posts: 1,897 Thanks: 0 Thanked 2 Times in 2 Posts	Well it was just a thought. I have a whine type noise which rises and falls with engine revs, more so in lower gears , which seems to disappear once in top. Probably other noises drowning it out. Dont get the noise when the Ac is off or in econ mod ie when Ac compressor is not in use. Never have got to the bottom of it but it hasnt got worse in 30k miles. A few others seem to have noticed the same thing cos there was a recent thread - about two/three weeks ago. Mines an Auto 75 2.5 but also had similar on previous Auto 75 2ltr (V6)

2nd August 2008, 21:52	#7
Simon Banned - Join Date: Nov 2006 Location: - Posts: 10,318 Thanks: 0 Thanked 4 Times in 3 Posts	Induction-type rumbles do not hide the noise... Trust me Like David describes above, there is a whine when the A/C compressor is in use - especially noticeable when the engine is cold. I also have whining noises associated with the power steering pump. Around 2200-2400rpm there is a pronounced resonant whine from the engine whilst under partial or full throttle - but this is just resonance from the air in the manifold and I don't think it's anything to worry about.