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Knocking noise on cold startup...help?

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Old 16 January 2001, 09:45 AM
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swa
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I seem to remember this question being asked before but I can't find it.

My MY00 turbo is making a rattley knocking noise on cold startup. It _maybe_ sounds like it is coming from the front right of the engine. It seems to have appeared over the last 2 months(or is it I only have noticed it until then?) This noise has reduced very slightly since the service where it got Silcolene Pro in it. The garage said that they could 'see' no problem. I think it would have been too hot/warm for them. They said to keep an eye out for it.

The knocking noise goes away when the car is warmed up. The only noisey bit when the car is warm is general noiseyness from all those cams and belts etc. (and a bit of ticking from each side)

The car runs better than ever now (9300miles).
Any ideas on what this is? And should I bother getting them to keep it in overnight?
Thanks
Swa
PS I won't be able to access the bbs again until Wed or Thur
Old 16 January 2001, 10:02 AM
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ColinU
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SWA,

Sounds like piston slap could be your problem (as discussed to death on this BBS!).

I have an MY98 (30K miles) with this problem (rattly knocking on cold starts). The other week one Scottish dealer said "it's piston slap on No4 cylinder, but not bad enough to do anything about it under warranty yet". I don't have much time for that dealership - 'cos they don't seem to have much time for their customers! I'll be taking it to another dealer later this week to see what their opinion is. If I have any joy with them I'll let you know.

- ColinU

P.S.
Where about in Scotland are you?
Old 16 January 2001, 10:08 AM
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Pete Croney
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I would definitely let your dealer have it overnight. It does sound like piston slap.
Old 16 January 2001, 05:41 PM
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scoobysnacks
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Hi all,

Hope someone can help because I've asked this before, but no-one has ever answered....
If you have an import (MY98 WRX) out of warranty that is suffering from piston slap, who can fix it and how much will it cost for either a short motor or a piston (or whatever) replacement? I guess the latter is the cheaper option, but is this recommended because I know dealers always replace the short motor? Finally, is it worth the expense if the car seems to run fine and the noise goes away when warmed up? Anyone?

Thanks for any help.

[This message has been edited by scoobysnacks (edited 16 January 2001).]
Old 16 January 2001, 06:16 PM
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firefox
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The choice to whether or not fix it, depends on the magnitude of the slap..and how many miles you want the engine to last.

The noise/damage will only get worse... piston slap is the base of the piston skirt impacting against the cylinder wall.. this damages the pistons.. but more importantly damages the cylinder wall....decreasing the sealing affect the piston rings has.

In your case.. you could either try and find a second hand short block (not that I would reckon that), or get over sized pistons fitted.

The cost wont be cheap... expect 600 for the pistons... 200 for new gaskets and misc stuff.. then there is labour to remove the engine..strip the heads.. bore and rehone the cylinders refit.

J.
Old 17 January 2001, 09:06 AM
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scoobysnacks
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Thanks for the info. So will the first signs of impending engine failure be blue smoke or dropping oil levels, or may it 'let go' without warning?
Old 17 January 2001, 02:22 PM
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swa
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Thanks for the info, the car is being looked at on Monday/Tue.

Does anyone have any good links for info on this subject?

Once the problem is fixed, then what is the warranty situation on my engine?

Also, what are the chances of reoccurance?

Have I been driving it too hard? (it always gets a good warm up and warm down.)

Colin - N. Ayrshire - also check your mail.

Swa
Old 18 January 2001, 06:51 AM
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Galaf
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I thought Piston slap was not supposed to happen on the Phase 2 engines used since MY99...

Laurent
Old 27 January 2001, 11:32 PM
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swa
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Smile

Car has been in to garage.
They replaced the cambelt tensioner as it was knocking against the metal cover. I presume they would have replaced the belt as well? It was sorted on warranty.
I think I read of someone elses MY99/00 having the same problem.

I guess the reason why the knocking noise went away on warm up was the expansion of the metal cover.

What a nice garage.....

phew....

[This message has been edited by swa (edited 27 January 2001).]
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