Low oil pressure quoestion

[Intlcutlass]

I have done a search, and it sounds like a couple people herer have replaced their sending units.

 

I am really going for a "What's your opinion?" poll here.

 

Latley, while sitting at a red light, my oil pressure drops to nothing.

 

As soon as I start moving again, all is well....

 

My 2.8 has 171,000 on the clock.

 

Here's the twist. only recently, I have been hearing a grinding noise that (to me) sounds like it's coming from the water pump. I last replaced the water pump about 6-7 years ago. It's hard to tell exactly, but it wounded like the wp to me.

 

I do change my oil every 5-6 thousand and use Mobil 1 synthetic.

 

SO...

Just a sending unit? OR , Is that grinding noise my worst fear (bearings)?

 

 

[1990lumina]

Mine drops down to 1/4 on the gage/little under 1/4 sometimes at idle...then while driving it's normally around 3/4 on the gage..

 

I didn't think you'd be able to hear bearings in the motor grinding...I'd say it's a sending unit...but then I'm not sure without hearing this grinding sound

[Q-Ball]

Mines goes to be 1/4 when not moving and just over 550 when driving. Off the scale.

[Supreme Cutlass]

Mine goes to a half at idle and a lil past 3/4 at normal.

[digitaloutsider]

Take the factory gauges with grain of salt. They're highly inaccurate.

[1990lumina]

To be sure you could plug in a mechanical gage possibly??

[Crazy K]

oil weight used?

filter type?

3400 swap time?

[ToroToro]

Oil pump could be dying...or you may have some debris in your pan that sloshes over the pick up when you stop. I had a lesabre where the previous owner had changed the pan gasket and must have stuffed the old one into the pan. Turns out it was plugging the oil pick up when I would come to stops. Just some thoughts.

[rockfangd]

heres the best thing to do. start with the easiest and work your way up till you find out what it i. The common dummy senders either read something or nothing, i took my real sender off of a 95 grand am. it is longer and plugs in the same way but you have to get the right one.

 

[attachment deleted by admin] Removed to free up storage space.

[Robby1870]

Yeah, take factory gauges with a grain of salt. If it really had no oil pressure, especially for an extended length of time, you'd hear something start knocking. Best way to check would be with a mechanical gauge.

[joey b]

my 2.8 had bad main bearings at 170K and I ran 20W50 in it to give it the added pressure at idle. With the 5W30 it would only have 2 ticks on the UB3 at idle and warmed up. The car ran till over 210K and even then it was still running but I suspect the Head gasket failed. The bad mains resulted in a very quite (almost inaudible) ticking noise when started on a 50* morning.

 

My point is that the oil pressure is not necessarily of great concern and you should spend the 20 bucks and 20 minutes to change the water pump.

[jeremy]

Take the factory gauges with grain of salt. They're highly inaccurate.

 

x3 ....and like joey b said, change the water pump

[rockfangd]

how difficult is a WP on a 94 cutty 3100

[Robby1870]

how difficult is a WP on a 94 cutty 3100

 

Super easy. Drain coolant. Take the cover off that has the belt routing diagram on it, take the belt off. Take the pulley off the water pump. Take the water pump out. Clean gasket surface, install new water pump. put back together.