For some reason or another there is a a LOUD knocking sound coming from my engine after starting it up on a cold days. It normally last for a few minutes until the vehicle is warmed up. I noticed that this only happens in the winter months when it's extremely cold outside. I drive a 2003 Infiniti M45. Please help!
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2003 Infiniti M45 Question: Knocking noise
Answer #1Superbob December 28, 2010, 15:26Master
It could be piston slap (loose pistons resulting from overheating, usually) or a crankshaft bearing problem. It could be some other things too so get it checked by a Nissan or Infiniti specialist.
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Answer #2Visitor, May 07, 2011, 23:43
silly question, but you are using Premium Gas right? if not, I suggest you do.
Answer #3danb99 October 02, 2011, 10:13Rookie
I have similar problems after cold cranking the car and moving it for a vary short distance and turning it off - next morning sounds like a rod bearing has gone bad - mechs indicate normal issue w/Nissan - Infiniti cars - wifes fx35 also does this.