Where is the oil pressure switch located on a 1985 nissan 300 zx 3.0

Intake manifold gasket.

No need to remove any relay. Proceed as follows:
- Park the car in shaded and well ventilated area.
- Remove the negative battery terminal.
- Loosen the fuel cap, fuel filter banjo bolt, push on or pipe clip.
- Wrap a piece of cloth around the connecting end of the pipe and remove the pipe.
CAUTION:
Let the engine cool down about half an hour before you proceed.
Keep your eyes away from the gasoline splash.
Keep any flame away.
Dry up the area immediately.
NOTE:
It is always better to get the job done by a qualified personnel.

pump isb behind the timing belt cover and is on the timing mechanism. all this has to be removed to change the pump.here is the engine diagram, that could be your problem. oil flush can sometimes fix this. and do a few oil changes with cheap oil and filters until it is clear.

Hi Teresa,here is the 3 links to change your oil pump,it says you have to remove oil pan and timing belt,so I will send you them,here's the oil pump removal guide.Here's the oil pan removal guide.Here's the link to the timing belt.Oops,here's how you remove the timing belt cover.Here's the oil pump.

Could be your oil pressure switch,here's a link.http://www.autozone.com/autozone/parts/Duralast-Oil-Pressure-Switch/1985-Toyota-MR2/_/N-ijxzlZ8znc6?itemIdentifier=261416_0_8450_ Here;s the location.http://www.autozone.com/autozone/repairinfo/componentlocations/componentLocationMain.jsp?fromSearchPage=true&categoryNValue=4294963411&categoryName=Oil+Pressure+Switch

It is built into the main engine control processor called the PCM and it talks to other modules, so it is not just one part.

Locate the alarm power wire and trace it from the alarm to the power source it is connected to and remove the fuse from the line or cut the line. If that resolves the problem the alarm is at fault. If it doesn't locate the kill switch and replace it.

injector relay is the problem there like a large fuse very easy to change

rear main seal is the leak to fix: drop transmission remove clutch, drop oil pan and replace seal. seal is about 30 bucks, if your not auto savy id let a shop do it.. prolly around 800 tho...

Check the digital dash power supply. You can find rebuilt, new or places that will let you send in your power supply and they will repair it for you. The cost ranges from about $50 to $150 US depending on wether you do the entire dash and power supply or just the power supply. The unit is fairly simple to access and replace just a couple screws and two pluges to take out. The power supply is a silver box about 3.5 inches x 3.5 inches x 2. inches thick and has two tabs extending from two oposite sides with a hole in each for the screws. The unit is located under the dash on the driver side just behind the botom plate under the steering column as best I recall going off memory.