I have the cobalt full sweep electric oil psi gauge. before, we had the half sweep sender hooked up and it was not reading, then i realized that i needed the full sweep sender, so we got that. we just gooked it up, turned on the car, takes a sec to pop up and read pressure. at 1st it was reading very high up, like 80psi at idle, which should be very very incorrect. we revved it up a bit, and it immediately shot up to 100psi, and then slowly went back down. we went out and took it for a drive, seemed to be working alright, got on it, and it shot up to 100 psi again. in the higher gears, like 3rd gear, it was reading around 80psi at lower rpms like 3k when floored, then gradually went up to 100psi.


i am thinking that the gauge might be busted. the sender is brand new and everything is hooked up perfectly. i had autometer send me out a harness because the one i had was messed up. so everything is brand new, except for the gauge.

 

your gauge should read 80-100 psi when the oil/engine is cold. when it warms up you should get 8 psi or more at idle.. no less than 8-10 psi though... My 03' with 45,000 miles puts out 25 psi at idle when fully warmed up. And this is @ 900-1000 rpms...

 

im just not sure if the sending unit is bad, even thoguh its new, or if the gauge took a crap

 

It is fine. When I first start my car up it reads 85 psi, then slowly drops down to about 10 psi over the course of a couple minutes (usually in 5 psi increments). When cruising it sits anywhere between 40 and 100 psi depending on load.

 

I will have to take a video of it tomorrow so you can see exactly what i mean ... it really looks messed up

 

no video yet, but what kind of pressure is everyone else getting? on cold start ups and drives, and regular driving on the highway etc...

 

Cold about 80psi idle slightly higher when its rev'ed

Highway about 50-60psi when warm oil takes a bloody lifetime to warm up....

 

when im driving at around 7-75mph, im getting about 80psi on the gauge. even when its warmed up, in 1st gear, just normally accelerating, it will go from like 20-30psi, to over 100psi, then when i shift, it will start around 60 or so, then climb up to 100 again.

 

mine sticks at 15 psi fully warmed up, cold its at 90

 

what about what it reads when you are driving?

 

Fully warmed up at idle I'm getting 9-10 psi. At 50mph it's in the neighborhood of 60psi and at 80mph it's about 70psi. Only when you're under boost will it climb up to 100-120psi.

 

This from the factory service manual........

"The filter must withstand a pressure of 1800 kPa (261 psi) [manufacturer's specifications] to avoid filter and ultimately engine damage."

So, yeah, especially in cold weather, you can see some high pressures.