Renault Megane Coupe-Cabriolet 2005 1.6 petrol - intermittent camshaft knocking

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Tue 22 Mar 2011 20:26
Renault Megane Coupe-Cabriolet 2005 1.6 petrol - intermittent camshaft knocking - tony g

hi,

can anyone suggest a reason for this problem

ive recently bought a 2005 renault megane petrol ,the car has covered just 35000 miles.

when the car first starts the camshaft appears to knock for a few seconds before running smoothly and quiet .The engine management light comes on and stays on.

ive had the oil and filter changed.used a fuel additive to remove any carbon deposit on the valves and had the camshaft sensor changed.the ecu light stays off after resetting until the engine is cold .When i start it from cold the camshaft ? knocks briefly and the engine management light comes back on .my mechanic says its unlikely the camshaft is worn because of the low mileage and because the engine/camshaft doesnt knock when the engine is warm. His only option now is to change both camshafts £600 .

has anyone encountered this problem before .any help would be much appreciated.

regards tony g

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Tue 22 Mar 2011 20:37
Renault Megane Coupe-Cabriolet 2005 1.6 petrol - intermittent camshaft knocking - cheddar

Not sure though I am thinking something like an oil return valve - the car starts, oil pressure does not rise as quickly it should causing the tappets to be noisy and the pressure switch tells the ECU that the pressure is low which causes the engine managment light to come on.

Take it to a Renault main dealer.

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Fri 15 Apr 2011 21:42
Renault Megane Coupe-Cabriolet 2005 1.6 petrol - intermittent camshaft knocking - tony g

Finally got to the bottom of the camshaft knocking problem , not the camshaft at all ,the dephaser was the problem,

never heard of it ? neither had i .it sounds like something from star wars .Its a toothed wheel that fits on the end of the camshaft ,and is driven by the cambelt.the wheel is filled with oil and as i understand it ,it works like a fluid flywheel ,it evens out the motion of the camshaft as the car starts ,anyway everything now runs as it should ,the total cost to repair was £450,better than the £600 to replace both camshafts,which probably wouldnt have sorted the problem . thankyou to everyone who read my original post .

tony g

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