Strange engine noise during cold starts

[DarkGreenQ45]

I have a 1997 Q45 with the 4.1L engine and during cold starts the engine makes a horrible grinding sound for about the first 5 minutes. After its warmed up the sound goes away and everything is normal. It only happens when the engine is completely cooled down. Does anyone have any theories???

[qship96]

oil level and condition? when was the last time oil was changed and what weight oil was installed? Sounds like it could be oil starvation since it only happens after cold starts.

[Mint Q45A]

And make sure you are using a good quality oil filter (OEM, or Mobil1)....

[Trumpkin]

It could even be a bearing. Idler pulley bearing, waterpump bearing, alt, but you would think the noise would stay. How many miles do you have on itt?

[Jim1999Q45]

Are you sure the starter motor is disengaging after start?

[SleepinTXQ45]

i would agree with all above, but.... if u can take off the accessory belt(drive belt), if noise still there, internal, & not saing possible but i have never ever seen a starter hang up for 5minutes&/or warm-up, but anything is possible, so start their

[Q451990]

It could even be a bearing. Idler pulley bearing, waterpump bearing, alt, but you would think the noise would stay. How many miles do you have on itt?

I second this theory... I had an idler pully on my old Q that would howl like a Ford power steering pump at startup. Very loud and annoying... but would go away. Far worse at cold ambient temperatures.

I would get a mechanic's sthesecope to narrow it down. They are dirt cheap at Harbor Freight (www.harborfreight.com) - especially you have a local store and get on their coupon list.

Heath