v6 vs oil pressure light at idle

[c@l@is]

HI .. I bought a cheap v6 vs a few days ago (250,000k) and have noticed the oil light sometimes flickers at idle, only does it when the engines at temperature & idle. Doesnt seem to do it any other time, not even cold start, seems to be perfect otherwise, no ticking or knocking, plenty of power & smooth.

The engine oil is full to the line & looks to be very clean but im unsure what weight it is.

Could it be the weight of the oil causing it ?.. would it be more likley to be sludged sump&pickup ?.. much chance it could be the oil pressure switch ?..

If it was a v8 I would think sump sludge for sure but being a v6 and seeing the oil so clean and rocker gears looking so clean kinda makes me think its probly not sludge ?

any help much appreciated, kinda hope someone out there has come across this issue before & can point it straight out

[Brett_jjj]

It could be the oil pressure sensor at the front of the motor near the oil filter.These can do this after the engine has been cleaned.Water gets into it.Maybe try taking the wire off and on a few times and cleaning the connection.It also could be the wrong oil in the engine,(to thin).

[stroked]

If oil pressure is dropping off when engine is at operating temp. and it's ok when cold, could be that your main bearings are worn or the wrong size has been put in. That's my opinion anyway. Good luck.

[c@l@is]

ok thanks ppl, I might drain the oil today for a start & see if its to thin. I know what your saying about the crank bearings but I have rattle tested this engine a few times now and cant even hear the slightest of a rattle?.. not that im ruling out the bearings im just living in hope that it might not be them.. The engine has not been washed for a good 10 years by the look of it so im not sure if the pressure switch would have got wet

[hako]

I'd do what you plan - change the oil and use 20W50 and a new filter.

[Paiste402]

ok if ur oil light is flickering mate thats not good with the buick/eco V6's. they have a sludge building problem, even if you change the oil every 5000kms it still builds up and then it gets into the pickup causing the light to just flicker at first even though the sump is full. I would try and act fast cause my bro had this happen to him and the car threw a rod, a mate of mine has had 5 of em go all the same too. Another mate of mine had his motor sieze solid from the same problem, light flickers then a week later the worst happens.

Run some flush through it please if you do change the oil, this doesnt always work but it does something. Idealiy i would remove the sump and clean out the bottom of the motor, that mate of mine who had his blow up took the sump off and found 2 litres of sludge at the bottom. This is a common GM problem, they have had this happen with other american motors where fully servied motors were throwing rods and siezing.