First off, to put my car into reverse easily without it grinding I have to put my foot under the clutch and pull it up and then press down and slip it into reverse. I may have to bleed the clutch or it could be an another problem. Second problem is that the temperature gauge on the dash does not go up at all after driving for 25 minutes. Just wondering what controls it and what needs to be fixed. Third problem, it is not a problem actually but just a question, when I press on the gas the oil pressure gauge goes up, is that suppose to happen? Also once the car is warmed up what is the proper oil pressure?

 

Mine does the same with the exception of the clutch problem. Bleed the clutch and see if that helps, might be time to replace the clutch master and slave. As for the temp gauge problem, Check your coolant level, and make sure the yellow (?) wire is connected tight to the coolant housing. Butt connector style connection if I remember right.

 

Well Chris it would be a big plus if we knew the year model of your car. it must be a stick if you have a clutch BUT n/a or turbo. put that in your signature like Audio and it will be there everytime you post. location good too might find someone close willing to help. Yes Oil pressure goes up with engine rpm and down with higher temp. not to worry much stock gages notorious for acting up. there is a sender that operates the temp gage they go bad.
Replace the master and slave clutch hydraulics saves a ton of bad memories changing them out on the side of the road at OH dark thirty on a rainy night (ask my son)
assuming you posted in the right section you must have a 280zx. here some general advice save you problems down the line: Get your battery load tested. Be sure you have clean, tight corrosion free terminals on both ends of your battery cables. Be sure the ground (negative) cable goes to a bolt into the frame before going to the starter. grounding through the starter is not a reliable connection. Z's don't like low voltage. causes the electronics to act funny. it is possible to have enough amps to crank but not enough voltage to run the electronics. If you have one size fit all cheapo clamp on terminals they are a problem waiting to happen.

Clean the connectors for the maf or afm, ecu and tps. Deoxit by CAIG is probably the best connector cleaner on the market. spray with CorrosionX after cleaning and before putting together this will help prevent any further corrosion.

Replace outer tie rod ends, and ball joints. replace the bushings with poly (don't forget to lube them as directed unless you like squeaky things). New shocks. Get new boots for power steering. all those things will make you think you are driving a different car. doing them piece meal is a waste you won't see a great improvement until you do the complete job. You need to get the car realigned after messing with the front. Have your tires in good shape and rebalance. Rear bushings nice too but more work and you won't notice as great an improvement. Rear shocks also because if the fronts are gone so are the rears. if car squats when you jump on the gas the rears are gone.

download the fsm from xenon. If you can find a chiltons or hanes cheap at the used book store they are sometimes helpful.

 

Under the thermostat housing is the sensor housing, there are 2 sensors that have the same connector, one on a pig tail, the other plugged directly in, swap those 2 and see if that fixes it, that's what fixed mine, the PO must have worked on it and got them reversed. here are some pics to show exactly what I am saying.