Oil Pressure Question

[KimsJeep]

Ok guy's I posted on the "what did you do to your TJ" thread about changing the oil sending unit because of the old one pegged to the right, then was staying higher then normal. When we changed it to a new "NAPA" auto parts sending unit, and changed the oil and filter, it started running lower then normal. Would run around 40 at running speed at first, then as it got hotter it would run about 30-35ish. It would drop to almost 0 when it a light. The pic is where it runs when at idle.

The other day I had to go into passing gear to pass someone before my lane ran out, I mean I floored it! When I came to the light a few 100 yards later, it dropped to 0 and check engine light came on. Once I started going, light went off and needle went back up again.

Today we hooked it to an actual pressure gauge. At first start up it ran about 40 psi , then once it got to running temp at 2000-2200 RPM it ran around 30 psi and when at idle it went down to 15psi.

My question is, Is the oil pump working correctly or should it be pumping at higher psi? I don't want to drive it if you all think the pump isn't pumping correctly. The original sending unit before it pegged, would run at a little over 40 psi, and would go down to about the first line between the 0 and 40 mark.

Should I try a different sending unit and if so, which one do you recommend?

Thanks for any help. Really wanting to start driving the Jeep now that it is nicer weather!

First pic is at idle.

Next pic is at running speed.

 

[KennethS]

Today we hooked it to an actual pressure gauge. At first start up it ran about 40 psi , then once it got to running temp at 2000-2200 RPM it ran around 30 psi and when at idle it went down to 15psi.

My question is, Is the oil pump working correctly or should it be pumping at higher psi?

Sounds right to me.

 

[TheBoogieman]

Today we hooked it to an actual pressure gauge. At first start up it ran about 40 psi , then once it got to running temp at 2000-2200 RPM it ran around 30 psi and when at idle it went down to 15psi.

13 psi at idle is normal. After that, it should increase and decrease with the rpms. In the 35-75 range. I'd go with a Mopar sending unit. Some people have good luck with Standard Motor Products also.

 

[KimsJeep]

13 psi at idle is normal. After that, it should increase and decrease with the rpms. In the 35-75 range. I'd go with a Mopar sending unit. Some people have good luck with Standard Motor Products also.

Thanks for the reply. I'm going to order the a Mopar one and see what happens. Now that the weather is warmer, it is dropping down to 0 at stop lights after about 30 minutes of driving. It does go right back up to about 30ish once I step on the gas. Just don't like that it goes to 0.