Oil pressure......Need help!

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Dec 27, 2009 | 07:19 PM

-ZIXXER-

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From: MO

Oil pressure......Need help!

Hey all, the oil pressure gauge started messin up on me today. It started fluctuating, but it only does it below 700 rpm. As soon as it is above 700 it goes back to normal. The truck doesn't sound diff and still runs perfect. Is it the sending unit shooting craps or could it be something else? Thanks for your help

Dec 27, 2009 | 08:27 PM

madpogue

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From: Madison, WI

Actually, it could be your oil pressure actually dropping below the "threshold" at low RPM. That "gauge" is actually an idiot light with a needle. The sender is a "switch". When there's sufficient oil pressure, the needle pointer goes right-of-center. When there's not, it goes left-of-center. The fluctuating you're seeing is the sender/switch opening and closing. So either the sender is indeed crapped out and switching at the wrong point, or the oil pressure is indeed dropping below the point where it trips the "gauge".

Dec 27, 2009 | 09:02 PM

-ZIXXER-

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From: MO

I guess I should have added, the fluctuation I'm seeing is the needle jumpin a million miles a second from the left of the gauge to the right of the gauge. It's not just staying in the normal range. It's going haywire

Dec 27, 2009 | 09:45 PM

oldbird1965

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From: AZ

If your talking about the stock gauge then you might have some trouble because that gauge is activited by only 6psi. If your oil level is up then you should hope your gauge is broken. Put a real gauge on and see what's its doing.

Dec 27, 2009 | 10:15 PM

c00nhunterjoe

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Joined: May 2007

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From: Belair md

best bet is test with a mechanical gauge, if you dont have one then i dont think the oil pressure sending units are expensive

Dec 27, 2009 | 11:23 PM

strokin'_tatsch

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Joined: Jun 2007

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From: Austin, TX

i would bet its the sender. if the truck is running fine then the LPOP should be doing a decent job of keeping the HPOP rez filled. if it wasn't your truck wouldn't be running good. i'd replace the sender and see what that gets you. if they are expensive i would throw on a mechanical guage to make sure.

The sender is on the HPOP rez incase you didn't know.