I haven't driven the car in a while and after a long trip, the oil pressure gauge would read 0psi at idle (1000rpm). After replacing the oil pressure sensor, the gauge still reads a little lower than I thought it was before. It'll read 11-13psi at idle and a little more than 10psi per 1000 rpm up untill 3700rpm where the psi to rpm ratio seems to decrease.

These measurements are on Mobil 1 10w30 in ~80 degree sunny weather.

I'm a little concerned as I'm not sure if I'm just paranoid, or if there's aire compressing up by the sensor so it doesn't get an accurate reading, or if I actually have a problem.

Also on a side note, if I'm parked and slowly open the throttle, the speedo will start to rise after 4000rpm (also right around 40 psi on the oil pressure gauge....)

 

on an ls1 the hot idle should be at least at 6 psi. I cant tell you what on an lt1 but it would likely be comperable. Also the sending units are weak and dont read really accurately in these cars. You should get it checked with a mechanical gauge.

 

Today I hooked up an Autometer mechanical gauge and hooked it up right above the oil filter and it typically read the same thing as the stock gauge (with the sensor in the stock place behind the intake manifold).

At idle, the stock gauge stayed around 20psi most of the time, while the Autometer gauge read just abover 0psi. Also, the Autometer gauge would rise a lot slower than the stock gauge, and also slower than the rate that the engine was increasing rpms.

Would a worn out, or somehow restricted oil pump cause this?

Thanks.

 

Yeah if you have one of the older oil pumps like the 98-00 LS1, they are notorious for going bad. I think the 01 and up got the updated pumps. Personally I changed mine to make sure that it wasnt the pump. Get a ported ls6 pump from one of the sponsors and change it out. Its not very difficult just time consuming, but I guess check out whether it would fit an lt1 first, I dont really know.

 

I'm not sure that they are interchangable, but there are a few different LT1 options (high volume, high pressure) that I'll be checking out. Thanks for your help.

 

6 psi? that sounds kinda low...i read in another thread that you should have about 10psi per 1000rpm to be in the clear.


my 98 ws6 idles at ~35psi at hot idle and goes past 50 at WOT around 5.5k rpm and i've got 128k on the motor