I replace a new oil sensor and had a change oil and filter, the check oil lamp light comes on, what could be the problem?

 

If you replaced the pressure sensor and you have oil in the sump, and the light is still on, you have no oil pressure or the wiring harness is bad. New oil pump or a crank bearings.

 

Check your pressure with a wet guage, it maybe issue with your pressure switch or as stated above ^^^^....get your tools out and check!

 

Did you have the oil light before you changed the sensor?

 

There are some good questions posted by other members above this post. We're here to help if you help us help you.

Here are some tips for changing or validating an oil pressure sending unit.

1) I used oil pressure sending unit socket like the one in the picture to remove and re- install the unit.



2) The factory installed sending unit came with thread wrapped in teflon tape. Some people replace Teflon tape with Permatex PTFE (Thread Sealant). It is good to use some type of thread sealant be it Teflon tape or Permatex thread sealant.



3) If you use a kit to perform an oil pressure test, be careful to test the gauge hose or male end threads with your sending unit to make sure you match the thread type. It turned out the oil pressure testing kit I purchased from Harbor Freight provided an exact match for the Nissan British Standard Pipe Thread (BSPT) thread type. The factory oil pressure switch is 1/8 BSPT whereas most american gauges will use 1/8 NPT. I have read about people damaging the BSPT threads when trying to connect a thread pattern made for an american car. The picture shows how I tested the new sending unit threads with the testing kit gauge threads.

 

^I didn't even know there was a special socket for that.

What's special about it vs a deep socket?

 

I don't know if there is anything special about it.. I don't have a lot deeps that large so it made sense at the time. Oh.. I think the deep I had wasn't deep enough or large enough to contain the sensor part so I had to make a trip to the parts store to get that socket to remove it..

The VQ30DE sending unit seems to be much easier to reach than the first Nissan engine where I learned to run a pressure test. Replacing that sending unit was almost as much fun as replacing the main 14mm power steering bracket bolt on our cars..

 

^Thanks for the answer!