ls1jeeptj

My motor (LS1) is only holding 25 PSI at idle and 35-40 under acceleration. Is this too low or within the acceptable range for a 75k mile motor?

PREDATOR-Z

Is it stock? Did you ever take the intake off or played in the back of it?
That is a bit low, but sometimes the sending unit (sensor) play tricks, I would check that first.

GR33N GoblinM6

iTrader: (14)

yeah that is low.. check all the easy things first..

ls1jeeptj

Motor is stock - just transplanted it into a Wrangler from a donor car and am running Autometer gauges so I am sure the gauge reading is accurate. Any difference in where the sender is located? I tapped the sending unit into the little bolt on piece near the oil filter - but I wouldn't think you would get any different reading there than on top of the block. And no the motor has not been opened up.

GR33N GoblinM6

iTrader: (14)

well the stock location for the oilsending unit is on the back of the top of the block.. im not sure if that oil plug has high pressure behind it or not.. i use than for my oil temp. you might want to try and T off the one the computer uses and see if its the same.. if its the same.. you might have an oil pump going south..

did you get the history of the car it came from?

ohsofast

iTrader: (6)

Why/What would cause the oil pressure to be low

PREDATOR-Z

look what is at the back!

http://www.ls1howto.com/howto/geniii...//IMAGE015.jpg

Ferocity02

iTrader: (60)

Too thin of an oil, too much bearing clearance, bad reading from the gauge. I think stock oil pressure is in the 40-70 range. Miner never drops below 40. Try running a 40-weight oil if you're not already. Many believe that 30 weights are too thin. Depends on the brand of oil though. I've found that Mobil 1 makes very good 30-weights. However, brands like Napa make TERRIBLE 30 weight oil. At running temp they basically become as viscous as water, which is pretty disconcerning.

ricethis

a safe minimum is usually 10psi per 1000 rpms

03 BUSA

iTrader: (25)

That statement is the one to listen too. This is usually an engine builders standard.

02TransAm/Batmobile

iTrader: (32)

i thought it was closer to 7.5 per 1000 rpms?

1baddls1

iTrader: (31)

+3

NHRAMAN

iTrader: (1)

ricethis

7.5-10 psi per 1000 is fine, especially on tighter tolerance motors like ls1. in any event, if ur ever in question in the accuracy of ur dash pressure gauge, or the OPSU, hook up a mechanical gauge to it......................

cobrakiller221

iTrader: (12)

My oil pressure ranges from about 50-80psi depending on the rpms and it has 92k miles.

MNR-0

40psi at idle and 60psi at WOT