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Please tell me, what do you think about gauge readings and about its flickering.
Is it normal or is there something wrong?
I hope the whole problem was just a sensor as Ranger (and others of you) predicted...
 

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You have plenty of oil pressure.
Not sure what to say about the bouncing needle. The gauge on my Road Runner is steady as a rock.
What happens when you raise the RPM a bit?
 

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Re: Oil pressure light on at idle.

Hot idle oil pressure is just fine. The flickering may be due to the short hose between the gauge and port. Nothing to worry about.

EVERY time some oil hole, port, idle speed change, whatever varies oil pressure by 1/10 psi an undamped gauge will flicker.
 

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Well, I am still here, still waiting for new pressure sender... Just to be sure I've ordered two, one from Rockauto, one from eBay, but no one arrived yet. From eBay expected ETA is august, 8th...
 

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Just as an FYI, I've purchased several items off of Ebay that claimed to be "GM" parts, only to find out that they where counterfeit. I'm starting to believe that is the case more often than not.
 

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Discussion Starter #47

Please tell me, what do you think about gauge readings and about its flickering.
Is it normal or is there something wrong?
I hope the whole problem was just a sensor as Ranger (and others of you) predicted...
That fluttering of the gage is exactly what I was seeing at all pressures with the AC Delco E-Core filters and as soon as I switched to a NAPA gold filter the fluttering went away and so did my oil pressure light problems. Have put about 800 miles on the engine since then and have not seen the OP light since. I think the AC filters were so restrictive and that was causing the pressure relief valve in the filter adapter to rapidly open and close causing the gage flutter and the OP switch didn't like that at idle.
 

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-Administrator- 2002.5 F55 STS 2014 FWD Explorer
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Samert's observation is the same as in other oil, auto, and filter forums - the E-Core filters, made by Champion Labs (branded for AC Delco but identical to other brands) seem to have internal media and/or bypass valve problems.

I have not personally taken one apart, just parroting other findings.

Study the link in Post 15.
 

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Hello everyone!
So I have some news for you. A new switch arrived, it should be original AC Delco, bought on eBay from Genuine Parts... Instaled and tested on short trip - everything looked fine.
Then a longer ride thru heavy traffic and... It started light again. On idle and very rapidly, no steady light, just repeating like strobo...
So again - car up, switch out, presure gauge in and more test and measure. Around 40 minutes of simulating of a ride, idle, move up to around 2500 and down again. During 2000 needle flutters around 60 - 70 psi (minimal limit is 35), on idle it is 10 - 20 psi (as on previous video, minimal limit is 5 psi). So I've took gauge to tests, just to be sure it shows real readings. Gauge is ok, tested.
Next step was another switch, now there is Airtex (one from two alternatives, what offered me RockAuto for this car and year). First short ride shows everything ok, but we will see. But I think it is good decision to order NAPA filter...
 

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I get the shut engine low oil pressure warning at lights when I sit a few minutes.. annoying.Im guessing each oil filter has a different bypass pressure.My oil monitor is at 68 percent so next oil change will get full synthetic oil and a six filter..if that doesn't cure the problem I'll swap out the sensor.
 

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Re: Oil pressure light on at idle.

Different car/engine from those discussed in this thread.

Can't hurt to try a WIX filter and maybe a JoeGibbsDriven 10W-30 HD engine oil.
 

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I am having a flickering OP light at idle in warm weather as well after about a 20 mile jaunt. I've never had any DIC warning, only the flickering of the OP light. It has 66k miles on it, always serviced as scheduled. I use Wix 51522 oil filters and Castrol 10W-40 high mileage oil. I replaced the OP switch with an AC/Delco switch and still have the same problem. I'm not that familiar with the Northstar engine, even though I've had this car for 20 years. It's never given me a problem and this is the only engine related issue I've encountered with it. I've not checked the OP with a mechanical gauge or checked the torque on the balancer bolt.

So I guess I should to retorque the harmonic balancer bolt and if that doesn't resolve my issue I need to test my OP with a mechanical gauge.

Thanks in advance!
 

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Unless the balancer bolt has been removed, it is not likely your problem.
I'd suggest you start by verifying the actual oil pressure with a mechanical gauge.
If that turns out OK, it's probably the switch.
 

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Re: Oil pressure light on at idle.

Northstar engine, GM/Cadillac service manual:

Hot engine - minimum pressure at idle - 5 psi. Minimum pressure at 2000 rpm - 35 psi.
...
Old thread but I'll ask anyway -- it seems a common situation for the low oil pressure warning to come on at hot idle and go away when applying some throttle. But increasing the RPM also increases the minimum pressure, so this means even the oil pressure actually was low it's increasing enough to pass the higher specification at 2000 RPM?

Since my second car has a tachometer I know that my internal sense that the motor is working too hard time to up shift, was already passed at 2000 RPM, but I don't know how automatic transmissions feel about this.
 

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In any normal internal combustion engine, up to operating temperature, engine oil pressure and delivery volume vary as a function of engine rpm. It is perfectly normal to see pressure go from maybe 8 - 10 psi at idle to 45 - 60 psi at 35 mph, then back to idle pressure at the next stoplight.

Delivery volume - hot oil - low rpm = low pressure due to necessary bearing clearances. High rpm = high volume = higher oil pressure.

Volume and flow are cooling and lubrication; pressure is not.

Transmission shift points depend on gearing and load at any instant. Flat road, slow acceleration - low shift speeds. Wide open throttle, max load = high shift rpm speeds Normal.

Yes, transmission fluid flow and temperatures factor in there, too. Sort of like engine oil works - but a bit different.
 
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