Vauxhall Corsa C - Corsa C 1.2 16V - engine noise

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Mon 6 Oct 2014 16:50
Vauxhall Corsa C - Corsa C 1.2 16V - engine noise - bootzey

Hi All

Thanks to respondents of my previous posts.

I've got a loud tapping noise from what seems like the rear of the engine. However this only happens after about 6/7 miles of driving. It doesn't happen if the car is left to tick over for a hour. The noise then disappears if the car is left ticking over after a drive. The oil light flickers on and off but only at idle in traffic...sometimes it's permanently on but only ever at idle. If left to idle after a drive the oil light also eventually goes out. Sometimes I get the noise but not the oil light and others I get both. The light and the noise both happen if the car is revved high when not diving, just sitting on the drive. Sometimes I can turn the engine off when the noise is happening and the oil light is on then restart it 30/60 seconds later and the noise isn't there and the light is out.

I've changed the timing chain etc but recently had to have it all off again because the water pump had to be changed and when it was removed there was rubber from the timing chain cover gasket mangled up in the pump!! I also found sealant in there to. I've had the sump off and along with hardened coke deposits there was sealant bits in the oil as well as the pickup filter. I've now got 10w40 and the car is great when cold and really responsive but makes lots of rattling with a cold startup before oil pressure builds up

There's also an Egr fault code sometimes as I do the pedal trick very regularly but the spanner light generally isn't on.

I can't understand why high revs start the noise off. It's almost like oil is backing up some where creating very high pressure in the head as I'm sure it's related to the exhaust cam and tappets. Or maybe high revs drag oil from the tappets making them noise. Either way, when left to idle the oil pressure returns to normal levels.

Help greatly appreciated as I'm totally confused with the symptoms.

Many thanks.

Dave

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Wed 8 Oct 2014 11:30
Vauxhall Corsa C - Corsa C 1.2 16V - engine noise - mjm

If the oil pressure light is taking its time to extinguish when the engine is started then it suggests that the oil filter is draining back into the sump. It is worth changing the filter for a good o/e one.

You have found contamination in the form of sealant and gasket bits in the engine. It is possible that these bits have found their way into the oil passages and are restricting oil delivery to some parts of the engine including the oil pressure relief valve. It is also possible that they are restricting the oil return passages from the head to the sump. This could cause the oil level in the sump to drop low enough to allow the oil pump to suck in air.

I think that you really need to have the oil pressure monitored with a gauge to give a better indication of what is going on.

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Thu 9 Oct 2014 13:15
Vauxhall Corsa C - Corsa C 1.2 16V - engine noise - bootzey

Thanks mjm.

Think I'll have a look at pressure gauge.

Went for a sedate (under 2500 rev) 12 mile drive yesterday...no oil pressure light on or noise.

Drove normally for 5 miles this morning (I.e. Over 2500, sometimes as much as 4000 revs) and the engine was noisy when I got home but no oil light as it wasn't completely warmed up.

I've also got a coolant problem in that with the heater on the engine doesn't get any hotter than 80 whilst driving.

Cheers

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