unstable oil pressure gauge (1 Viewer)

[landarcht]

I'm curious what's causing my oil pressure to indicate this low (see attached photo) even cruising on fwg. at about 60 mph, my foot is lightly on the accelerator. I recall before it usually stays I the middle.
Recent had routine full maintenance and mechanic didn't notice anything out of the norm.
Car feels, performs and sounds normal.

 

[Bardiya]

Oil pressure sender unit is probably bad, very common.

 

[Spike555]

I'm curious as to how hot it is where you live and I assume he changed the oil too,l and if so what weight and quality motor oil did he use?

 

[Tahomatom]

Super easy fix. Located next to the oil filter. Napa had it stock and took me 20 or so minutes. Longest part of the job is skid plate removal and reinstall. I was around 75 at Napa. 170-200 at Toyota and Lexas. Lexus was cheaper then Toyota.

 

[landarcht]

Actually, the oil sender unit was replaced about 4 months ago because the gauge was completely dead, at least not it revived it, but the pressure seems very low. I called the mechanic, they said it could be that oil pump is malfunctioning? Is that possible? Oil level seems fine too.

 

[landarcht]

Also, what's likelihood of the instrument cluster going bad? How much would it cost to replace it? Not cheap I take it?

 

[Spike555]

Actually, the oil sender unit was replaced about 4 months ago because the gauge was completely dead, at least not it revived it, but the pressure seems very low. I called the mechanic, they said it could be that oil pump is malfunctioning? Is that possible? Oil level seems fine too.

What oil and oil filter did they use?
How hot is it where you are?

Cheap oil will effect oil pressure.
The wrong weight of oil will effect oil pressure.
A cheap oil filter will effect oil pressure.
Ambient temp will effect oil pressure.

 

[landarcht]

Toyota OEM filter and oil, 5W-30, it has been pretty hot here in So. Cal w/ day temp. in the mid 80-90's

 

[Spike555]

5w-30 is only good upto 95*F, after that it is beyond when it was designed to handle heat wise.

5w-30 is nothing more than a good enough for 90% of people out there solution to engine oil.

 

[Jeepster09]

Easy test, just get mechanical guage from auto parts store [some have rental or loaner guage] remove factory sender screw it in [test guage] where sender went and start it up and see what actual pressure is.

 

[landarcht]

Here's latest. I drove from So Cal to Nor Cal last night and kept monitoring oil gauge's behavior and noticed this: Upon start of engine and going on fwy. it will be at middle position while cruising for about an hour then starts to gradually go down. It will tick up during acceleration but will back down eventually to lowest tick mark on gauge. Not sure what's the issue, a reliable mechanic told me it could be the instrument panel and the electrical voltage drops at that gauge. I don't notice any other odd behavior or sound or smell and oil level seems fine, sender unit has also been replaced. I rather not want to go through the cost of replacing the panel. Could this be oil pressure pump needs replacing?
Any advise would be great.

 

[Jeepster09]

I would not worry about it. Erratic guage operation unfortunately is somewhat normal and why most manufacturers do not use guage and only have simple light. As long as you feel engine ok, learn what is normal for your guage readings and forget it.

 

[landarcht]

Ok. The gauge basically has been operational for up to when I hit about 100k then it started to act erratic. Also notice the temp gauge has been very stable, staying just below the the middle level even after driving for 5 hours straight, didn't warm up a bit. Last week So Cal has been close to 100 degrees, temp hasn't moved a bit, wondering if the temp gauge is going out too?