Oil Pressure Switch

[c4markee]

Good Morning. 2011 Jetta TDI
Cars going into the shop tomorrow for the oil pressure light coming on. But figured I would ask a few questions.
It only comes on if its been sitting a few hours. Overnight sometimes or if I don't go out at lunch.
I did an oil change and fuel filter change Saturday. At the same time I swapped the switch hoping this was the issue.
I noticed when I did the oil change the canister emptied itself into the oil pan. Is this normal? My truck I have to pull it out.
My thought is since the stupid switch is on the canister maybe the can is emptying in the hours it sits and the light goes bling.
It only goes off long enough for me to shut it down, check the oil and than start it. No sounds or ticks, than it runs fine. Shop first thought it was the sensor being gummed up.
Thoughts.

 

[c4markee]

Well goes in at 1 today soonest they could get me in. Gave me the story that it has to repeat while there. Didn't do it this morning.
Noticed too my fuel economys gone down Ive been averaging only 40's on my drive to work and the drive to see the girl on the weekends. Work is a country highway so 55-65 and one stop.

 

[c4markee]

And they cant get it to repeat go figure. Anyone else have an issue with the oil pressure light? Seemed it only happened after the car sat for a period or it was cold. (below 30).

 

[993er]

And they cant get it to repeat go figure.

Did they at least test the system with an oil pressure gauge to make sure it isn't the pump or pressure relief valve?

 

[c4markee]

Since they could not get it to repeat they could not put the time into it. Such crap.

Did they at least test the system with an oil pressure gauge to make sure it isn't the pump or pressure relief valve?

 

[c4markee]

How can I test the pressure relief valve?
This tends to be when cold.

 

[993er]

How can I test the pressure relief valve?
This tends to be when cold.

It is what regulates the pressure in the system, be it hot or cold. It will vary of course within a range. For example on one of my cars at idle, at start-up I get 5 bars and when hot, 2.5 bars. (1 bar = 14.5 psi)

 

[c4markee]

Would I test this by hooking up my oil pressure gauge to where the switch was to be able to read this? Anyone have a procedure with required pressure for the 2011 jetta.
I was looking at the P3 Cars vent gauge to see if there are separate wires available for me to wire in a pressure sending unit and read with that.

 

[993er]

Would I test this by hooking up my oil pressure gauge to where the switch was to be able to read this?

That is one possible location.

So does this only happen on start-up or once underway as well?

 

[c4markee]

Typically when I first start it and get underway. I usually have it in gear and am moving but not out of my short driveway.

That is one possible location.

So does this only happen on start-up or once underway as well?

 

[993er]

As you mentioned the oil canister emptied itself.

This sounds like any first start-up after an oil change when there is a lag till filters initially fill.

I'd check the installation.

 

[c4markee]

It was doing it before my recent oil change.
It hasn't done it since the day after I changed the oil. So thinking maybe it was still gunk in the passage for the oil pressure switch. The switch itself seemed pretty dirty / had gunk in the pressure passage.
Weekend was pretty cold here. I don't think the dealer seated the oil filter properly last time I brought it in.