OIL PRESSURE LIGHT

Re: 1995 Saturn:

A couple/three months ago my oil pressure light started coming on only
after I first started the car and when I would approach the first road
incline. But, it has come on more and more often ever since then -
sometimes even on the highway briefly.

I'm assuming it will eventually be on all the time. I also assume it is
faulty. But, since I may be wrong, I'm posting this.

Any advice would be appreciated. Allergic to repair shops.

Len

 

Replace the oil pressure sensor ASAP. If the warning light no longer comes on,
rest easy in the knowledge that you had a defective oil pressure sensor.

However, if the warning light continues to illuminate, get the car to a repair
shop immediately and have it checked out -- the oil pressure probably really
*is* low, and continuing to drive it in that condition will ruin the engine in
short order.

You *have* checked the oil level, haven't you?

 

The oil levels are fine.

Where is the oil pressure sensor located?

Thanks.

Len

 

The oil levels are fine.

Where is the oil pressure sensor located?

Thanks.

Len

 

Don't know -- what engine do you have?

 

Doug:

I have a 95 SL1. I need to know where the oil pressure sensor is located
and the obvious next question would be, does it take any special tools to
replace it, and do you have any idea what they cost?

TIA

Len

 

I'm not sure exactly where it would be on that engine, and there isn't really
any "typical" location to look in. On some of my vehicles, it's been low on
the side of the block... OTOH, on my Dodge truck, it's all the way at the
*top* of the block.

Anyway, according to my Saturn wiring diagrams, you're looking for a tan wire
with a black tracer that goes to something like this:

http://www.partsamerica.com/ProductDetail.aspx?&mfrpartnumber=OPS168

It would appear that the only tool needed is a wrench or socket of the
appropriate size. Certainly, that's all I've ever needed, the four times I've
ever needed to change an oil pressure sensor (on three Dodges and one Fiat).

 

I believe that the oil pressure sender is located on the rear side of the
engine block, facing the firewall, and between the alternator and the knock
sensor. It may be different on your '95, but this is where I recall seeing
it on a '96.

I believe that you can test the resistance of the sender (center conductor
to the engine ground) and it should vary 15-80 ohms with higher resistance
for higher oil pressures (rev the engine).

If you unscrew the sender unit, then you can directly screw in a good old
mechanical oil pressure gauge and see the actual pressure. I'd recommend
you do this before deciding to replace the sender. By the way, these are
known to occasionally fail and are the usual cause of the idiot light
illuminating. That said, given the serious consequences of low oil
pressure, it does not pay to guess so you should really check it using a
real mechanical gauge.

Good luck and post the results.

Bob

 

Yep, that's where it is. No special tools really needed. If you google my
name with oil sender saturn you will find that I had about 5 of these things
leak on me. They are about $10 at NAPA, $35 at the dealer. Since they kept
failing quickly, all were replaced under the warranty. I finally installed a
oil pressure gauge (electric sending unit) thinking that I had high oil
pressure. Pressure was normal and it does not leak, so that is what I use
now.

-David