# Oil Pressure drops DRAMATICALLY when cruising on highway.



## BoBakTXL (Aug 30, 2004)

sup guys

on my 86 non-turbo z, when cruising, or driving on the highway, AND ONLY on the highway or freeway, if the motor is at a continous 2500-3000 and even other rpms (2500-3000 is usually what i drive at though, which is between 60-70mph), the oil pressure guage starts to go down, and down, and down, until it finally rests at 0. Thats when I push in the clutch, let it either idle, or start to rev it up with no load on the motor, and the oil pressure slowly goes back up when idling or moderate slowly/medium speed goes up when just free revving the motor.
what the heck is wrong?
by the way, the motor has been checked for enough oil, and also the motor burns oil....
Wtf?


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## asleepz (Feb 24, 2004)

Well I'm going to say your gauge is wrong... If your engine had no oil pressure at that RPM for over I'd say 30 seconds, it'd be fried and locked up.


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## BoBakTXL (Aug 30, 2004)

uhhh....
so dont worry about it?

is it safe to stay at 4000 rpms for like 20 mins (going 100 mph on freeway for 20 mins) or am i risking blowing the motor up?


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## asleepz (Feb 24, 2004)

well like I said, if you can even get the engine up that high without it instantly shutting down and locking up you have oil pressure. An engine doesn't last long with it. I'd say your gauge, wiring, or sending unit is screwed. If it has done it multiple times and you haven't had a problem your ok.


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## jmcguire (Sep 16, 2004)

Change your oil sending unit.If you can't find it I will look it up in my shop manual.Let me know . Jamie


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## asleepz (Feb 24, 2004)

It's on the left side of the oil filter...


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## Marc Z31 (Jul 25, 2004)

The sending unit almost always gets gunked up and reads incorrectly on Z31's. Get a new one or clean the old one


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## ICP Sux0rZ! (Jan 10, 2005)

bobak u saw my video, i was doing that for prolly 100+ miles over 90 the whole time my car runs fine, no lost oil


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## asleepz (Feb 24, 2004)

The point of changing out the oil pressure gauge with an aftermarket one has been brought about countless times. Can anyone provide a parts list of everything you need to do it?


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