car sounds like its not getting oil first 20 seconds when cold
have a 2003 grand marquis . on cold start up the motor revs high and sounds like its low on oil. after 20 seconds it idles down and sounds fine! oil is full and changed regularly .
If you have over 100K on the engine it could be n oil pump pressure relief valve partially open causing it take longer to bring it up to pressure or the oil pump is getting weak, it would be advisable to have the oil pressure checked both cold and hot, that would tell you if you need to go further with any repairs.
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