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  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
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High oil pressure.. Strange flux.

  • Thread starter Thread starter MusPuppis
  • Start date Start date Nov 11, 2005
M

MusPuppis

New Member
Nov 8, 2004
136
0
0
Lexington, Ky.
Nov 11, 2005
#1
  • Nov 11, 2005
  • #1
Ok.. my engine is a 92 5.0. Ive checked codes and nothing is coming up.

Its developed very high oil pressure. Just a hair under the hash mark at the max of the guage for a while now.. Well, this last week its gotten worse. I started the truck the other day and the damn oil pressure pegged the guage, the dropped down to its usual place (still high of course).

Now, this has happened several times since. The pressure will literally max out on the guage and the engine seems to get a little pissed at this point. Oddly enough though, when I get on it a little bit the pressure DROPS to completely normal levels.. but as soon as I level my speed and the RPM's drop, the pressure rises again to those high levels.

I'm pretty damn sure this is bad for my engine, heh, so the truck is parked till I figure this out. Any suggestions? Could it be as simple as the filter failing or does this sound like a pump related issue?
 

DMAN302

My mom says thanks for the pearl necklace.
Nov 8, 2003
2,120
2
59
windsor, Canada
Nov 11, 2005
#2
  • Nov 11, 2005
  • #2
Once I saw you were discussing the stock gauge reading...I stoped reading. The stock gauge is little more than a dummy gauge, get a true reading oil pressure one in place then you can decide what's really going on. Old motor in place my stock gauge would read nicely in the middle warm idle...apparently reading in the middle actually meant well under 10PSI..not good.
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
31,179
34
129
Nov 11, 2005
#3
  • Nov 11, 2005
  • #3
Man, good to see you posting again in here.

I am with Derek - your truck's gauges could very well be what is causing this.

A 10 buck OP gauge from the parts store (put it inside the cockpit, put it under the hood, return it later, etc.) will reveal what is going on. Or if you have a spare, hook it up real quick.

That is all I got. take care bud!
 

Autobodypro_1

New Member
Sep 30, 2005
76
0
0
Florida
Nov 11, 2005
#4
  • Nov 11, 2005
  • #4
The stock gauge is probably giving erratic readings, unless you inavertently put 50 wt oil in. If you have mechanic friend have him temporarily hookup a mechanical pressure gauge to verify proper oil pressure, then change the sending switch or the gauge itself. If it remains high, the bypass spring might be stuck closed
 
M

MusPuppis

New Member
Nov 8, 2004
136
0
0
Lexington, Ky.
Nov 12, 2005
#5
  • Nov 12, 2005
  • #5
Allrighty,

I'll find a better guage and get a real reading and post back. I know its not just the gauge malfunctioning though, becuse when the pressure spikes so severaly the engine bogs down and once or twice my CE light popped on for a split second (but left no codes in memory.. =/ ). The truck drives angry (if that makes much sense) when the pressure is spiking.

I'll see what I can do about a real reading.

Yeah Hissin, I'm back - hehe. Been working on rebuilding my Z, havent done anything to the truck, cause till this little problem its run flawless. Other than my cold start problem.. Its still there. I've given up on it. Ive replaced every sensor from one side of the block to the other. I've cleaned, checked, adjusted or replaced everything I could think of causing the problem and gone over the engine with a microscope. Only thing I can think of anymore is the ECU has some bad data or something. Ive reset it several times, maybe its a hardware issue. Who knows.
 
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