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Misfire and knocking

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Old 02-26-2010 | 09:05 PM
  #61  
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Just tried it, the sound is still there after holding it at 1400 rpms for 3-5 seconds. It goes away after 5 minutes once the engine begins to warm up.
Old 02-26-2010 | 09:15 PM
  #62  
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lifter.... should go away once its lubed up.
Old 02-26-2010 | 10:19 PM
  #63  
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Originally Posted by kst_77
Just tried it, the sound is still there after holding it at 1400 rpms for 3-5 seconds. It goes away after 5 minutes once the engine begins to warm up.
Does the noise return upon next cold, warm, or hot engine start?

If not then I agree with others: zero lash adjuster (lifter) bled down or doesn't pump up fully for a few minutes or so. Once engine fully warmed up a spirited drive could help. This helps to flush oil from the lifters and replace it with "fresh" oil.

Once the noise goes away it should stay away. If it returns after engine has sat a while then a lifter is 'bad' in that it allows oil pressure and oil to be squeezed out when engine off. Assuming of course the engine stops with the lifter under compression. It may not. Random. In this case a new lifter may be required. I came across a new Carrera (an 02) that required this and in fact had it done under warranty. Happens.

If the noise comes and goes at any time engine running... that's tougher... I'd have to think about it but only if you tell me it does this.

Keep fresh clean oil in the engine. Old contaminated oil loaded with unburned gas and water will lose viscosity and then is more prone to leaking out of where it shouldn't.

Sincerely,

Macster.
Old 03-01-2010 | 07:49 PM
  #64  
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The noise comes back only at cold start, looks like the lifter. They are going to try Swepco first. Will keep you posted.

Regards
Old 03-19-2010 | 06:40 PM
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Swepco the oil did the trick, the noise is gone. Thank you everyone for the help.

Regards
Old 03-19-2010 | 07:34 PM
  #66  
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Originally Posted by kst_77
Swepco the oil did the trick, the noise is gone. Thank you everyone for the help.

Regards
Good to hear. Swepco oil (what viscosity?) or Swepco oil additive?

Porsche techs have told me that Swepco oil additive -- the one with moly (I forget the Swepco part number) -- quiets engines on startup that are used infrequently.

I tried some in each car but I didn't notice any difference. But I don't let my cars sit unused for more than a few days at a time and noise on startup is not a problem.

Sincerely,

Macster.
Old 03-19-2010 | 08:20 PM
  #67  
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Originally Posted by kst_77
Swepco the oil did the trick, the noise is gone. Thank you everyone for the help.

Regards
I'll bet you're sleeping better now. Nice to hear that something simple did the trick.
Old 03-22-2010 | 06:25 PM
  #68  
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I think it was Swepco 502, worked like a charm. Yes sleeping much better :-) thank you once again for the help.



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