My oil light stays on for a few seconds after a cold start, not after the engine is warm.
2003 discovery 101k. The VIN is not in the bad oil pump range. I had the dealer remove the oil pan 29k ago when the light was flickering at low idle. Then the oil pressure went from low to good after a cleaning. Now have switched to synthetic oil 4 k ago.

Thoughts?

 

Stop driving it till you can leave it over night with a shop so they can do 4 oil pressure tests, idle when cold, 2000 RPM's when cold, idle at operating temp and 2000 RPM's when warmed up.
If all is goo then you most likely have either a cheap oil filter or a bad oil pressure switch. What oil filter do you use?

 

Not sure. What ever the shop put on

 

Saying you have an 03 with an oil light sends everyone into panic mode. Thoughts of failing oil pump come to mind immediately. The switch to synthetic may have dislodged some sludge in the engine that got sucked into the oil pump and blocking flow. Definitely have the pressure test done to verify if it's a bad pressure switch (which is likely at 101k) or if it is a real problem.

 

The oil light staying on for 5-10 seconds after a cold start is nothing to worry about, it staying on for 30 seconds is.

 

Touch the throttle some and the light goes off in seconds.

I will take it in tomorrow.

 

Nobody asked about the grade of the oil.... he says he changed to synthetic 4k ago? There were some changes before. Is it possible that the grade of new oil is the cause?

 

I say its the oil filter.

 

I had the oil changed, and put a K&N 3001 filter in. So far it is good.

 

Awesome.