Mike Whetzel

I need help. I'm new to the ls1 game. My car at start up runs 40 psi and wot 60. But warm idol about 25 to 30 psi at 209 degrees. No knocking or anything. It goes to 40 when I hit the gas. Car has 143 on her. Thanks for helping. Nervous just picked her up last weekend.

RPM WS6

iTrader: (3)

Sounds quite normal to me.

Auto trans cars have a bit lower OP readings at idle than manuals, as their idle speed in gear is 30% lower than manuals.

'98-'00 cars have the older oil pump, which also tends to show lower readings than '01+ cars with the revised LS6 pump.

SouthernRex

That sounds like where mine is. Once it warms up the viscosity changes and the pressure reflects that. I hope you aren't going WOT before the car warms up, though. lol

murphinator

iTrader: (2)

my 98 is on the low side like yours been like that since I got it about 3.5 years ago , has 155k now haven't hurt it yet and its still quiet cold , hot ,etc...

Cajun ELESS-ONE

seems normal to me. as long as its over 15-20 psi and hot idle its good. if it concerns you, get a melling standard volume high pressure pump and put it in. not to hard to install.

Michael Yount

iTrader: (1)

Data point -- brand new LS3 crate engine -- @ 210F oil temp, 28-35 psig idle, rev the motor and instant increases up to 60-65 psig depending on rpm.

RevGTO

iTrader: (12)

Also the ribs on the inside of the pressure sender wear over time, giving lower readings. My pressure bumped up when it was replaced during a rear main seal job.

Bartrking

My 06 with 143k on it sits about the same and I haven't had any issues. I do think I have a lifter problem now that starts ticking and then goes right away every once in a while

z28_YOU_HO

iTrader: (7)

My car is 40 at cold idle and 15-20 at hot idle lol... You're fine

RockinWs6

Honestly if you are reading the factory gauge it doesn't mean very much other than you have oil pressure. It could be accurate or it could be WAY OFF. Only way to tell is to have it tested with a calibrated gauge. I personally wouldn't give it another thought. You're fine. I have high oil pressure readings and the engine is a bit noisy so there you go, my oil pressure could be anything but as long as the gauge moves I know its got something. I smoked alotta bananas in the 60's and I still have oil pressure.............

z28_YOU_HO

iTrader: (7)

UPDATE - I switched out my oil pressure sending unit over the weekend. 60 psi cold now and 40 hot. That's probably your problem

Chevyguy2001

Was it difficult to do?

z28_YOU_HO

iTrader: (7)

I was switching to a LS6 intake manifold, so it was easy for me. I hear you CAN do it without removing it if you have the right tools however.