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knocking and pinking - what's the difference?   
Are they the same thing or different? Pinking is a sort of ping sound isn't
it? One of my dad's old cars did it once and my dad couldn't hear it cos his
hearing's buggered but me and my mum could and he didn't believe us til the
garage told him.

Anyway what causes pinking and what's the difference from knocking?
Date:Thu, 15 Sep 2005 06:16:50 +0000 (UTC)   Author:  

Re: knocking and pinking - what's the difference?   
The message <dgb3ki$mn3$1@nwrdmz02.dmz.ncs.ea.ibs-infra.bt.com>
from "neutron" <neutron(abcde)@f.off.com> contains these words:


> Anyway what causes pinking and what's the difference from knocking?


Pinking is the fuel igniting too early and the pressure meeting the
piston coming up making what I've always thought of as a "ticking"
sound. Usually caused by the ignition being set too far advanced for the
conditions, though there are other causes.

Knocking is the fuel igniting at the right time but burning explosively
instead of smoothly. This was why lead was added to fuel - tetraethyl
lead absorbs infrared strongly and prevents the radiation from the
initial ignition setting the rest of the charge off in on go. Can be
caused by all sorts of things, but the wrong grade of fuel is a good
place to start.

-- 
Skipweasel.
In the beginning was the word.
And the word was Aardvark.
Date:Thu, 15 Sep 2005 08:00:03 +0100   Author:  

Re: knocking and pinking - what's the difference?   
So does the pinking noise usually happen at low revs or high revs when
timing is wrong?

And knocking happen at all revs? If the CAT gone, will that cause the
knocking noise?
Date:15 Sep 2005 05:01:53 -0700   Author:  

Re: knocking and pinking - what's the difference?   
wrote in message
news:1126784099.947780.31860@z14g2000cwz.googlegroups.com...

> So does the pinking noise usually happen at low revs or high revs when
> timing is wrong?
>
> And knocking happen at all revs? If the CAT gone, will that cause the
> knocking noise?
>


Pinking is most noticeable at low revs when accelerating, i.e. when the
engine is under load. That's when I always notice it anyway.
Date:Thu, 15 Sep 2005 16:06:34 +0000 (UTC)   Author: