# 03 Oil Light & Oil Pressure Question



## Samahi72 (Feb 14, 2008)

Thinking about buying a 03 Frontier. The oil light comes on but it isn't lit very brightly. You really have to look at it to see that it is barely on. What do you think is going on? Where is the oil sending unit located on this truck and what kind of oil pressure should be there when the truck is idling and at running rpms?
Thanks


----------



## SPEEDO (Jun 9, 2003)

stupid question... have you checked the oil?


----------



## Samahi72 (Feb 14, 2008)

SPEEDO said:


> stupid question... have you checked the oil?


Yes, Oil was just changed.


----------



## azrocketman (Oct 5, 2005)

I'd still check the oil; shops are known to screw up. Are you using the specified weight (5W-30) oil? How many miles on the engine and which engine?

1) Is the light dependent on engine rpms?

2) Is the light on at night with the panel lights off?

3) Does the light come on full brightness when you turn the key to on without starting the engine?

Steve


----------



## Samahi72 (Feb 14, 2008)

azrocketman said:


> I'd still check the oil; shops are known to screw up. Are you using the specified weight (5W-30) oil? How many miles on the engine and which engine?
> 
> 1) Is the light dependent on engine rpms?
> 
> ...


4 cylinder, 110K
Don't know what oil weight the shop put in. The light barely glows but it is constant regardless of the rpms. I noticed the light during the day with the panel lights off. I didn't try it with the panel lights on. Nor do I remember if it came on full brightness with the key on (engine not running).

I was thinking of disconnecting the wire from the sending unit and seeing what that does, and replacing the sending unit. 

The engine seems to be just fine, no lifter or rod noise.


----------



## SPEEDO (Jun 9, 2003)

is your alternator charging? and up to spec's?


----------



## Samahi72 (Feb 14, 2008)

SPEEDO said:


> is your alternator charging? and up to spec's?


Alternator appears to be okay, none of those gauges gave any reason to suspect a bad alternator.


----------



## Louis138 (Nov 19, 2007)

This sounds like a voltage leak to ground. If I remember correctly, the light gets 12V+ from the ignition switch when on, and the oil pressure switch provides a ground path when pressure is below a few PSI. It should either be on or off. If you have a dim light, the sending unit could be bad or there could be a weak short in the wiring between the sender and the light.


----------



## Cusser (Apr 16, 2004)

Temporarily screw in a manual pressure gauge where the sender goes, and confirm that there really is oil pressure there. Then worry about the sending unit.


----------

