bags142

Sorry for the novel..



Ok... changed my oil to mobil 1 high mileage 10w40. Ran fine for a week. Drove 300+ miles to CMP, no issue.

Did saturday hpde in hell or the hottest temps in recorded history. Oil was between 270*-280* off and on all day pressure was fine. Drove back to hotel and then back to track sunday, no issues.

1st track session sunday after ~10 min, my oil pressure went to 18 psi. Got oil warning light. Went from 15 psi- 50 psi. Freaked out and starting thinking about how I was gonna have to walk back to Atlanta and then pressure came back up. No smoke, no noise, no loss of power.

Pitted in ASAP and checked oil level. Well within normal range. But, "low" for track use. Put in almost a full qt and Drove around all seemed well. Went back on track and was good for 1 lap. Then same thing all over again. Took the car out on the street, and oil psi was good until redline and then would drop down to 4 () psi. Again, no noise, no smoke, and oil temp was staying at 230*

Decided that if motor was going, might as well see how close to Atlanta I could get

Drove the 300 miles back to atlanta with oil psi readings from 2-70 psi , did not matter on rpm range or throttle postion. BUT, mostly lost oil pressure when more than 1/2 throttle. And temps from 226*-238*. Made it all the way home! woohoo.. NO oil leaks that I can see.. and no smoke or loss of power.


Now.. I am trying to figure out where to start.

Oil sending unit is less than 2 years old from o'rileys.

I have read about the o-ring on the oil pump from the pickup tube and the spring in the oil pump.


So.. I was thinking about starting with draining the oil and see if there is any metal in it. Then look at the oil pump o-ring.

Good start or is there something else I should do?

Thanks

EDIT...Changed oil pressure sensor and it fixed the problem

cliffs.. at hpde weekend got low oil pressure (4 psi) and oil psi is now between 4 psi and 60 psi at random rpm and throttle position.

geerookie

That's where I would start. I replaced the o-ring and now I have 50 - 60psi at idle (cold) and 40 hot.

Steady 70 psi hot at redline.

Screamin Z

At VIR we had a simmilar issue.

Oil pressure went from 50-0 PSI. Changed out the sending unit and all was well.

bags142

Thanks... drained oil and could not find anything with a magnet. Hacked open filter and could not find anything in there.

Thanks, that is exactly what I am going to change.

Then if all is well do a blackstone and see what they say after ~500 miles.

bags142

Well, I put in a stock GM sensor and have driven it a few times.. almost 100 miles and have had no low oil pressure warnings.

Thanks eveyone

Screamin Z

Good to hear!