Does Failing IMS make a knocking noise

All 996 C2 46,000 miles. Performing perfectly. Out today car driving fantastic and smooth. Pulls up in a car park only to hear strange knocking noise from engine. Goes up and down with engine but can’t pin point it. Can’t hear when driving on the open road. Oil pressure is good. Car uses no oil. Could this be caused by a failing IMS or an effect of? Will be contacting Porsche on Monday to get car in.

Hello is it a knocking noise or a more ticking sound like the tappets ? My tappets started to play up but did clear after a good run and an oil change, recently I left my car at work and was moving it in and out of our warehouse daily and they started to tick from lack of use then cleared once it had a good run. I did did however take it to OPC they said it would be an engine out job. But an indie recommended what I did above which saved a fortune. I would recommend getting a couple of opinions. Let eat us know the out come. Phil

First off, a failing IMS is very unusual, despite what you read on the internet. Until you rule this out, you do not want to use the car. A simple check you can do is drop the oil and filter and look for debris. If the IMS is failing, there will be a lot of debris! Normal causes of engine noise ... in our opinion - #1 noises from aux belt pulleys / alternator #2 noise from water pump #3 hydraulic lifters, when cold Overall - remember that the IMS is the unlikely option ... but it will get worse very quickly. Kind Regards Lee

All I am aware it is unlikely to be the IMS. Also from what I know there is no warning usually. In answer to the above responses which I appreciate. Defiantly not a ticking tappet, I have a Cayman which has a lazy tappet if car is left and know this sound well. Noise is there when hot and cold. The knocking noise is accompanied by a generally rough sounding engine. (In transit everything sounds normal but noise may be drowned out by vehicle motion Also dipping the clutch has no affect so not clutch, flywheel or gearbox etc. Car is probably going into Porsche Bristol on Tuesday. Fingers crossed Only driven 1300 miles since purchase from Porsche Cardiff (Third party warranty supplied because of age, not holding my breath on this being any good) Car Purchased November 2017 Car was Porsche Approved. Love the car. Thanks Again

Trevor, Thinking optimistically, it could just be something as simple as a component working loose..! As said, probably best not to use it too much and get it checked over by Porsche Cardiff. The Porsche Approved Warranty seems to be quite comprehensive for engine and transmission related problems and hopefully should cover most eventualities. Jeff

Jeff unfortunatly car is to old for Porsche warranty supplied with 3rd party (Auto-protect). Car is 2002 registered Not planning to use other than drive it in Hope your right

My money is on the water pump, they can make a really expensive sounding knock when the bearings fail...

Cayman295 - Any update?

Hi Car at Bristol Porsche. Waiting for them to look at it. They rushed it in as soon as they herd it but could not diagnose it. As car was not previously booked got to wain’t for a slot. It got significantly worse on way to garage. They don’t think it’s engine internals. Water pump favourite but they not heard one make noise as bad as this. Once I hear I will publish the news. Appreciate your interest.

Water Pump should be covered by Warranty Mine was. (Although mine was a drive failure rather than pump) It actually a very easy job on a 996 drop the bumper and it all easy to get to Longest thing is refilling water and bleeding it If its not a warranty job a lot of the change will be coolant which iis silly money from Porsche Good luck they are very noisy and go regularly

Hi All Had confirmation today problem is the water pump. Great relief I can say. Cost of repair £800 to £900 Autoprotect warranty have agreed to pick up the bill so thanks to them i pay the bill and they refund if it goes through ok then a warranty company that actually honours its claims Will update if I get the money Trevor

Great result!

It's almost worth factoring in a pump change at a certain age. Good news and thanks for the update.

Mine went a few years back the big advantage was i got home all OK. i bought a new one from OPC and got my local guys to fit it as they have done a few on 911s think it cost me all in around £400 if that. At least you will have it done and dusted for the future. Regards Phil

All Got car back yesterday everything back to normal cost of repair £863.0. Luckily being paid by warranty. Thanks Cayman295

Autoprotect paid out in full no Agro at all Might be an alternative warranty if people want it for older cars Thanks

Now my RPM warranty has expired, I may give them a look-up. Ta Mark

If its done 1300 and is less than a year old you should be able to REJECT IT Porsche will not like Porsche centre selling a car that is NOT FIT FOR PURPOSE You do need to advise them that that you feel it should be fixed under warranty Both the above term are legal Good Luck