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Discussion Starter #1
What's the correct oil pressure for the GTV6 when idling at operating temp?

What about at 3000 RPM?
 

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If you are referring to your oil pressure guage in the car I believe the technical assumption is if it goes up as the revs rise all is OK. In other words the guage is not accurate. I dont know the specification for an accurate measurement using a suitable guage.
 

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Discussion Starter #3
Thanks - I was afraid of that answer. Is there a way to fix it, or just not worth bothering?
 

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But Mad North-Northwest
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Fix what? You need to clearly state your problem.

What is the oil pressure you're seeing and at what conditions? Are you using the stock gauge or an external gauge?

If you're using the stock gauge, nine times out of ten oil pressure problems are the gauge sender.
 

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When cold, if the gauge and sensor are working correctly, the gauge should read at the top of the range, on the far right. When the engine is at operating temperatures, at idle it will be below the left side low mark. On mine, when cruising at 3000 RPM, the gauge sits right about 50#. GUBI is right, usually the oil pressure sending unit goes bad.
 

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Waste of time and money changing the gauge or sender unit. Neither will ever be accurate. If the gauge goes up with engine rpm then its fine. Alfa engines have excellent oil systems (exclude boxer) so If you have a oil pressure issue your going to know about it because it will be something very bad. If you want to accurately monitor oil pressure get yourself a quality after market sender unit and gauge.
 

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The 'rule of thumb' for oil pressure is about 10 psi/1000rpm - up to the relief valve's set point.

As others have stated, the Alfa gauges are more 'general indicators' than absolute measurements. With a cold engine, oil pressure should show on the gauge within a few seconds of starting and it will typically be near the relief's valve set point even at idle. Once fully warmed up, oil pressure at idle will be much lower - some Alfa gauges will point to barely above zero. If your car has one and the low oil pressure warning light is not lit, then I wouldn't worry about it. If oil pressure should ever register very high I'd make sure the sender is OK (they are the weak link in the system) and if so, then I'd worry the relief valve is stuck open (not good).
 

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Is my gauge wired wrong, no oil leaks at all, revs go up, pressure goes down. I have always thought bad sender, just haven't go around to. Oil light works great.

ncng
 

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ncng... a oil leak wont cause a loss of oil pressure unless its horrific. Your gauge could be inaccurate for so many reasons ie: sender unit, loose connectors, bad earth ect ect. If you have an oil pressure issue you will know about it. Death rattle and eventual engine failure. I kind of look at my oil pressure gauge as an oil temp gauge. When its reading bugger all at idle the oil is nice and warm. As an anecdote i was having fun on a b road years ago when the wire from the oil sender came off giving me a bad oil pressure signal...my heart stopped as I pulled over only to be relieved that the spade terminal was loose.
 

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Just for comparison: I have "great pressure" on the gauge when cold between 55-75 and almost none when warms up. My pressure in the engine is fine though. If it shows when cold and moves with revs, you should be ok.
 

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My oil pressure is between 10 and 100 at about 3 times per second non stop. The needle looks like a mexican jumping bean. I tried two gauges, two different sending units and two different Engines. Actually it pegs out over 100 when its cold slowly comes down within 5 minutes then starts it dancing show for the rest of the day. Guess I just gotta live with it.
 

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Discussion Starter #13
Thanks everyone. I'm new to the car and wasn't sure if the needle being to the left of lowest mark was normal...sounds like it is, if there is such a thing.
 

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But Mad North-Northwest
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Yeah, that would be negative oil pressure. Probably not a normal occurrence, no.

It's most likely the sender. Replacing it is a bit of a b-tch, or some folks (myself included) have had luck drilling a small hole in it to get it working again.

http://www.alfabb.com/bb/forums/164-168-1991-1995/52549-bad-oil-pressure-sender.html

Or you can just live with it. Personally I like it working so I can monitor for any gross changes.
 
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