Hi everybody,
I've a Peugeot 106. It has run about 170,000 Km. On uphill a knocking sound of the engine is observed when more power is required.
Can somebody please enlightened me about this knocking sound?
Knocking Engine
Moderator: RichardW
<blockquote id="quote"><font size="1" face="Verdana, Arial, Helvetica" id="quote">quote:<hr height="1" noshade id="quote"><i>Originally posted by jeremy</i>
Is it petrol or diesel, what size engine and car model and any further information that you are able to give will help.
Is the problem road speed related or engine speed related?
Jeremy
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It's a 1124cc petrol powered engine.
Well, no, it doesnt look like a bearing noise.. May be my vocabulary has been wrongly chosen.... it's a 'clicking' sound instead of knoking sound. And this happens when power is needed e.g accelarating on a steep uphill road.
Is it petrol or diesel, what size engine and car model and any further information that you are able to give will help.
Is the problem road speed related or engine speed related?
Jeremy
<hr height="1" noshade id="quote"></blockquote id="quote"></font id="quote">
It's a 1124cc petrol powered engine.
Well, no, it doesnt look like a bearing noise.. May be my vocabulary has been wrongly chosen.... it's a 'clicking' sound instead of knoking sound. And this happens when power is needed e.g accelarating on a steep uphill road.
A CV joint is a constant velocity joint and are to be found in the front driveshafts. They wear with age and the outer ones normally make a noise when the steering is turned to full lock. the inner ones tend to drum. This noise can be load dependant.
You are referring to pinking or pre-ignition or knocking. This can be caused by bad timing, bad engine design (as in BMC Minis etc) poor fuel, weak mixture or simply a dirty engine. The noise is generally due to the shock wave generated when the mixture explodes in 2 places and the two explosions meet.
We still don't know the age of your car but I'm sure it has electronic ignition. How this is triggered will depend on the particular model of car but its probably at its correct setting. The pinking could be caused by incorrect plugs (or worn ones for that matter)
High speed pinking is potentially destructive and can cause pistons to burn and other problems. It might be worth trying it on a different fuel and see if this improves things (many years ago I had a VW Scirrico GTi that was allergic to Esso but OK on Shell) or trying one of the higher octane petrols to see if there is any difference. (Shell do one)
There can be many other causes like minor air leaks into the manifold from breather pipes that have slackened with age.
Jeremy
Jeremy
You are referring to pinking or pre-ignition or knocking. This can be caused by bad timing, bad engine design (as in BMC Minis etc) poor fuel, weak mixture or simply a dirty engine. The noise is generally due to the shock wave generated when the mixture explodes in 2 places and the two explosions meet.
We still don't know the age of your car but I'm sure it has electronic ignition. How this is triggered will depend on the particular model of car but its probably at its correct setting. The pinking could be caused by incorrect plugs (or worn ones for that matter)
High speed pinking is potentially destructive and can cause pistons to burn and other problems. It might be worth trying it on a different fuel and see if this improves things (many years ago I had a VW Scirrico GTi that was allergic to Esso but OK on Shell) or trying one of the higher octane petrols to see if there is any difference. (Shell do one)
There can be many other causes like minor air leaks into the manifold from breather pipes that have slackened with age.
Jeremy
Jeremy
My car 7 yrs old running about 175 000 Km. It has electronic ignition, and singlepoint injection.
Ok.. i've understood about the cv joints. No, the noise is not from the CV joints. It's in the engine itself and is accelaration dependent. Well, by accelaration here, i don't mean that a change in velocity but by demanding power from the engine during acceleration. It's more likely to be preignition or pinking. It's not the bad timing. I have had the timing belt replaced myself and am sure it's 'tip top'
.
May be poor fuel, weak mixture or simply a dirty engine. So how do I fix that without dismantling the whole thing. Will TC Injection of ECOtech do the thing?
This noise is not cornering dependent. It happens when I press hard on the accelarator when going uphill, where more power is demanded for a rapid increase in velocity.
And how does a worn out spark plug can cause that if the gap between the electrodes are properly set with the electrodes properly cleaned?
Ok.. i've understood about the cv joints. No, the noise is not from the CV joints. It's in the engine itself and is accelaration dependent. Well, by accelaration here, i don't mean that a change in velocity but by demanding power from the engine during acceleration. It's more likely to be preignition or pinking. It's not the bad timing. I have had the timing belt replaced myself and am sure it's 'tip top'
. May be poor fuel, weak mixture or simply a dirty engine. So how do I fix that without dismantling the whole thing. Will TC Injection of ECOtech do the thing?
This noise is not cornering dependent. It happens when I press hard on the accelarator when going uphill, where more power is demanded for a rapid increase in velocity.
And how does a worn out spark plug can cause that if the gap between the electrodes are properly set with the electrodes properly cleaned?
Pinking can be caused by hotspots in the engine igniting the fuel and in effect doing the sparkplug's job for it. In extreme cases the engine runs on when you turn it off - as it doesn't need a spark!
If the plug is of the wrong heat range it may run hot and cause pinking. Similarily if it is dirty with a deposit on it - and sometimes when they are worn out the centre ceramic for example has burnt away and may cause it to run hotter. Plugs are a simple and relatively cheap item to maintain in good condition and so making sure yours are good is an elementary precaution.
Cheap oil may burn and produce excessive ash in the combustion chamber which then glows - similarily valves near the end of their natural life, low oil level may mean the piston crowns are hotter than intended, some fuels are more prone than others - this is one of the reasons that lead was used in fuel - not for fun as some people seem to think.
A weak mixture will tend to burn hotter - and so it is possible that you have a minor air leak in your induction system - a check is an easy thing to do.
Jeremy
If the plug is of the wrong heat range it may run hot and cause pinking. Similarily if it is dirty with a deposit on it - and sometimes when they are worn out the centre ceramic for example has burnt away and may cause it to run hotter. Plugs are a simple and relatively cheap item to maintain in good condition and so making sure yours are good is an elementary precaution.
Cheap oil may burn and produce excessive ash in the combustion chamber which then glows - similarily valves near the end of their natural life, low oil level may mean the piston crowns are hotter than intended, some fuels are more prone than others - this is one of the reasons that lead was used in fuel - not for fun as some people seem to think.
A weak mixture will tend to burn hotter - and so it is possible that you have a minor air leak in your induction system - a check is an easy thing to do.
Jeremy
No, I don't have air leaks in the breath hose but what I can see is that drips of oil travels from the cylinder head cover to the single point injection through the breath hose.
It seems unsual but some mechanics have told me that I don't have to worry about that. Is it true? and does it contibute to the pinking or clicking whatever...?
It seems unsual but some mechanics have told me that I don't have to worry about that. Is it true? and does it contibute to the pinking or clicking whatever...?
A breather hose from some part of the engine internals to the intake just downstream of the unjector assembly is normal as getting the engine to burn the smelly fumes is as good a way of getting rid of them as any. I would sometimes expect to find some form of oil separator in the circuit (looks like a can or round disc thingy) to prevent too much oil getting through but this does depend on engine design. Often these tubes are very oily and this is nothing to worry about but in extreme cases the fumes could dilute the mixture causing it to be weak. The connections on this pipe should be tight as loose joints will let air in which could weaken the mixture.
Jeremy
Jeremy