blackfairladyz

OK so Im pretty sure my oil pressure sending unit is going out, it reads like 7 psi at idle after warmed up and about 70 at WOT. I know I have the right oil in it because I drained it and refilled it to make sure it was full. I was looking and the 350z units are around $70, but the ones for the g35s are alot cheaper. Arn't they the same motor? And would the g35 one work on the 350z? If you know anything about this I would appreciate the help. Thanks

Abdulrhman Khal

maybe your oil pump is not working good

blackfairladyz

I dont think so because It was fine one day and then the next I went to start my car and it read low. I never hit red line or the rev limiter. theres not reason it should be that is it?

winchman

The only way to verify the oil pressure is with a pressure gauge in the port where the sensor goes. That will tell you if the sensor is bad.

Or, you could just replace the sensor to see if the reading comes back up. It's a fairly common issue on the forum.

I'd jiggle the wires first to rule out a bad connection to the sensor, though.

blackfairladyz

Ok thanks winchman. Ill give that a shot.

tylerxfire

iTrader: (15)

when my sending unit went my pressure read sky high at idle and even higher while driving..never low...just way high..doesnt sound like ur problem but also i know i didnt pay 70 bucks for my unit..search on here there are many links to where to buy it, cant think of it off the top of my head right now..

Cass007

iTrader: (34)

This is your solution. Put in the mechanical gauge and check pressure. If the gauge matches what you were seeing in the car, turn it off and go have a cry cause your f%$#ed. If the gauge reads normal pressures then just replace the stock OPSU, $70 is nothing in the grand scheme of things.

I have no idea if the Z and G parts will interchange though.

str8dum1

iTrader: (11)

the G doesnt have oil pressure gauge, just a dummy light pressure switch. hence the difference in price. its not the same part

blackfairladyz

Sweet, thanks for the help.

(tylerxfire) when my sending unit went my pressure read sky high at idle and even higher while driving..never low...just way high..doesnt sound like ur problem but also i know i didnt pay 70 bucks for my unit..search on here there are many links to where to buy it, cant think of it off the top of my head right now..

I have read that that has happened to quite a few people, but I have alos heard that it can read low. Im PRAYING its the OPSU! But I guess Ill go ahead and buy the part and find out because I do not have a guage to plug into my block

blackfairladyz

Ok so I bought the OPSU and replaced it, it read the same -_-. SO i took it back off cleaned it up and returned it . SO I changed my oil because it looked really black and thin only after 35xx miles on full synthetic mobil 10w-30. It reads a little higher but still not like it used to. I have ran out of ideas and do not know what to try next, Im probally going to take it to a nissan dealer and have them run a full inspection on it. Thats $60 that i do not want to spend. So before I take it to them does any one have any thing else I could try, and has any one else had this problem before? I never hit the rev limiter on my z, I drive it hard now and then but always take care of it. So please help me.

Me staring at my car ->

winchman

Knowing the age of your car and the mileage would help.

There could be a problem in the triple meter or the gauge itself. You really need to get a pressure gauge to see what's going on. That's what Nissan is going to do.

Is the pressure higher on a cold start?

blackfairladyz

Its a 2004 with 94k on it. And yes it is around 50 on a cold start at idle. It used to be at 75ish at a cold start.

Alex Tappin

Ever figure this out? I have the same issue and even replaced the sending unit and it reads the same. I hooked up a mechanical gauge and the pressure is NORMAL! This either means the new unit I got is bad or the electrical connection to the sensor is bad.

DeusExMaxima

iTrader: (1)

My gauge is pegged on above high all the time. Im guessing its the sending unit. I just called and its $71 from Autozone. Im curious is the gauge and the oil pressure light work off the same sending unit?

Alex Tappin

Buy one off of ebay. It should be about $20 dollars. And yes, the pressure light works off the gauge, not the sending unit. You could have a flaw in your gauge and it would show the low oil pressure light in your car.

Alex Tappin

I have been having the same issue as the OP had. My oil pressure IS okay (i have hooked up multiple mechanical gauges and tested it), just there is an issue with the connection from the sending unit to the gauge.

HRMoneyPit

My HR always reads low too. Been meaning to check that out

Alex Tappin

Checkout this thread https://my350z.com/forum/maintenance...2003-350z.html

I post a few pictures of what I did to check out my oil pressure. Basically, bought a mechanical gauge and tested it that way!

Question for you... When you start your car up, does your oil pressure gauge start up (the needle starts moving) slower or faster than the voltage gauge?

nizmo_0385

iTrader: (5)

Same im 5-7 psi lower than whats reccomended

HRMoneyPit

That link said 14 PSI is normal and 40 over 2k. I think I'm in spec then