Oil Pressure Light Issue

[89SHOMAN666]

Hey All,
I have been having a problem with my red 94 ATX for about the past 4K miles. Out of know where driving down the road the oil pressure light will illuminate. Sometimes it does it at idle other times when it is in drive. However it is always when the engine is around 800-1500 RPM. I do not believe that it is a rod bearing issue as the motor is extremely quiet and smooth, however it is very disconcerting to get an oil pressure light randomly illuminating.

The oddest thing is that if you change the oil you get the short 5 second period where engine makes noise and then it immediately gets quiet again. The other bit of info is that is that if I shut the motor off and start it right back up again the light will also turn off and stay off for about 30 sec then turn back on again.

I am thinking it’s the oil pressure sending unit but I was hoping that maybe someone here had a similar problem.

Any thoughts or suggestions would be great.

Thanks,

 

[40BelowSummer]

Hurry and replace the sending unit and see if that solves the light. Or get that oil pressure gauge you've been wanting to get for your SHO and see what the oil pressure really is. I believe the light comes on about 5~psi (i think) and lower.

 

[Mr95Gl]

As stated above, change the Oil Pressure sender ASAP. If that doesn't solve your problem, park the car, and get the Rod Bearings done. While your in there inspect and make sure there's nothing clogging the oil pump. $60 later, your car will thank you for preventing a premature self-destruction. Good luck!

 

[Redskull]

The oddest thing is that if you change the oil you get the short 5 second period where engine makes noise and then it immediately gets quiet again.

come again? That doesn't sound like any oil change i've ever done.

 

[SHOtimer]

come again? That doesn't sound like any oil change i've ever done.

He is talking about before all the new oil has been pumped into the filter and the rest of the motor......I've had that happen on older cars, and some new ones. I also crank my SHO after an oil change to pre-prime the oil before I fire it.

Doug

 

[thecrew2999]

yeah a good thing to remember is when you change the oil to disconnect the DIS on the passenger side of the intake and crank it for a few seconds and then wait and do it again then reconnect it and fire it up... also recommended if it sits for awhile... that way all the oil gets pushed around the engine so your not putting and unneeded wear on your engine...

 

[Electricat]

That sounds very much like the issue my SHO had when I got it. I was getting low oil pressure, but if I shut the engine off for a few seconds, then started it back up, the pressure would be near normal for a minute, then back to low.

I tore into it to replace the rod bearings, suspecting that was the problem. What I found was a bunch of sludge in the oil pan....which explained my slightly odd symptoms perfectly: the crap was plugging the pickup screen, and when the engine was shut off for a minute, it would fall back into the pan....allowing normal pressure.....until it got sucked up into the pickup screen again.

I did replace the rod bearings while I was in there, and my oil pressure has been normal ever since. The old rod bearings were in decent condition, only showing a small amount of copper....definately not enough wear to explain my problem. I am quite confident that the chunk/gunk getting pulled into the pickup was the real source of my low oil pressure.

 

[SonicRiot]

It sounds as though you may have a sludge issue. Pull the pan an inspect.

My old '98 Windstar had an oil pressure problem eerily similar to yours. I found the 3.8L's headgasket leaking water into the oil. Just some food for thought.