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Discussion Starter · #1 ·
My car used to idle at around 30psi steadily once fully warmed up, but after my last oil change has been dropping down as low as 18psi steady and seems to bounce around a lot more too (between 14-20ish). Triple checked oil levels and all connections, it's right at the full mark and everything is tight. Should I be worried or is this a relatively safe / normal idle oil pressure?

What's the lowest oil pressure you guys see at idle once the engine is fully warmed up?
 

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Running 5w40 on the speed3...idle @ operating temp (~185-degF) = avg 28psi
Running 5w30 on the speed3...idle @ operating temp (~185-degF) = avg 23psi

Just for kicks 5w40 on speed3 ... cruising at 3000rpm @ operating temp = avg 70psi


I'd suggest probably checking the senders.
 

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I'm in the same boat as sok, run around the same pressure plus or minus a pound or 2.

Cold mornings -11 degrees, I'll idle around 90psi when I first start it up for about a minute.
 

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Discussion Starter · #5 ·
My cold and cruising pressures are similar, high 80's cold start for a minute, 70ish cruising at 3k. Just weird that it has dropped so low at idle... i wish i had a temp gauge, i'm thinking it's actually heating up more than it should. 5w30.
 

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hum i forgot oil i had in, but thats where i was at once the car was warm:
 

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Discussion Starter · #7 ·
I guess I just won't worry about it unless something else starts going wrong... it still runs great, that's all that matters right? I may just try a 5w40 on the next change to see how that affects it.
 

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hummm i think it was castrol 5w40... i think...
i don t think that my lower CR would influence the PSI.
 

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Discussion Starter · #9 ·
Yeah I don't think so either. The weird thing is that it bounces around like crazy at idle... between 15-25psi, very quickly. It used to hover right around 28psi steadily, and I have no idea what changed. If there was a problem with the sender, wouldn't it also be unreliable while driving? Because it's dead on accurate and the same as usual in all situations other than at idle.

Part of me wants to get it checked out with a good mechanical gauge, part of me says don't worry about it. It runs great and the last UOA was excellent and the engine never overheats at all, so... nothing to worry about, right?

Also, I'm definitely gonna try a 5w40 next time, I'm going to be doing a few track days in April/May so I'll probably switch to it right before the first one.
 

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Discussion Starter · #11 ·
[quote author=eurotuner link=topic=137714.msg2973483#msg2973483 date=1236106417]
do it 500 miles before you track day..
[/quote]

The track is 6 hours away (420 miles), so that's why I'm doing it right before I leave.
 

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Discussion Starter · #13 ·
If I hold the RPMs around 1000 it stays around 30psi, the sender seems accurate. It just drops to 20ish when totally warm at 700 RPM.
 

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buy a cosworth high volume oil pump.
 

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Oil pressure isn't something i would "just let go untill something elce goes wrong" i wouldn't drive it until i knew for sure it was the sender. imo.... Also the dealer recommends, for an 05, the oil pressure should be at 75psi at 3k rpm, while in neutral. No oil pressure means bye bye motor...

Btw ever since i got my car, my stock oil pressure sender hasnt been connected and i dont throw anys CELs or anything, so dont depend on it.
 

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Discussion Starter · #17 ·
[quote author=3driverPA link=topic=137714.msg3025926#msg3025926 date=1238384008]
Oil pressure isn't something i would "just let go untill something elce goes wrong" i wouldn't drive it until i knew for sure it was the sender. imo.... Also the dealer recommends, for an 05, the oil pressure should be at 75psi at 3k rpm, while in neutral. No oil pressure means bye bye motor...

Btw ever since i got my car, my stock oil pressure sender hasnt been connected and i dont throw anys CELs or anything, so dont depend on it.
[/quote]

My oil pressure at 3k RPM is right around there. If there were any problems with oil pressure while actually driving or revving I wouldn't drive it, but it's perfect in 99% of situations. It's just lower than usual at ~750 RPM while idling. Even blipping it up to 1k RPMs it'll go up to ~35psi like it should.
 

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anyone have any ideas why my stock oil pressure sender not being connected doesnt have an effect on my CELs or anything?
 

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[quote author=3driverPA link=topic=137714.msg3026711#msg3026711 date=1238430122]
anyone have any ideas why my stock oil pressure sender not being connected doesnt have an effect on my CELs or anything?
[/quote]

Nothing?
 
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