Technical Low oil pressure warning

[PuntoEvoCam]

Hello my oil pressure light recently came on. To try and overcome the issue I have checked the sump feeder wipe was blocked it wasn’t neither was it cracked/damaged in anyway. I have also cleaned the sump and done a full service on the car including new oil, oil filter etc I also put a new oil pressure sensor on it to see if that was the issue but the light and warning is still coming up? Anyone have any ideas what else it could be?

Car is 1.4 8v engine

 

[GrandePunto PL]

A lot of unnecessary steps (probably). First thing to check was the wiring. ECU wants to see a CHANGE after the engine starts.
You can simulate this by doing short-circuit with piece of wire (by yourself, start the engine and go the sensor plug and short it to the "ground").
And check the pressure switch (oil "sensor") with multimeter or test light during engine start.
Finally (really, the very first thing to rule out), measure the oil pressure.

 

[kbdeluxe]

A lot of unnecessary steps (probably). First thing to check was the wiring. ECU wants to see a CHANGE after the engine starts.
You can simulate this by doing short-circuit with piece of wire (by yourself, start the engine and go the sensor plug and short it to the "ground").
And check the pressure switch (oil "sensor") with multimeter or test light during engine start.
Finally (really, the very first thing to rule out), measure the oil pressure.

Hey this sounds like a good test. is this the steps?
1-unhook sensor connector
2 - short sensor (2 wire) connector by running wire from one hole to next
3 - ohm meter the sensor in engine
4 - start engine. - observe ohm and see if it changes ?

shorting sensor will tell ecu what? zero resistance and will trigger the light? not sure i understand , can you re-explain . ty

 

[GrandePunto PL]

There is nothing to explain. It's a simple-stupid pressure switch.
If it's NO (normal open) or NC (normally closed) contact (I don't remember 100%), doesn't matter, that's a trivia to figure out.

Oil pressure is crucial here and it's a very basic thing to measure (easier than compression for example).

ECU wants a signal CHANGE right after startup, that's why there is a "T" connection in the video above (not just pressure gauge and the sensor dangling freely in the air - you'll get warning message on the dashboard LCD screen and maybe limp mode or something like that, if you want to do a test drive).