multiple questions about my 300zx

[johnshop]

si i got this high mileage 300zx for cheap i think ( 2100 bucks) knowing it needed fixing. so i got to it.

i did a whole rebuild from the lower intake manifold up, new gaskets, replaced a dead injector, and a bad ignition coil, anyhow, with that i fixed the funny idling the car had.

now there's more trouble. and i have some questions.

the car is leaking,and i think one of the leaks is the rear main seal, and there's another leak on the vtc cams seals i think, the leaking is not bad, maybe a couple of drips overnight from the rear main seal and the vtc cams, is it safe to run the car like that? my actual oil pressure reads 60 when cold and goes down to the second line from the left when at running temp, the oil does build pressure when accelerating, all the way pass 60psi. is that normal? again, would it be safe to run the car like that? i will do an oil change some time next week, any specific oil i should be using/ buying? also, until i can cash out the dough to repair the leaks, are those stop leaks additives any good? or should i just walk past them and never look or think about them again?

another question is, and i seen some topics in here about it but i would like to be reassured, my knock sensor is out, the car in first gear has little power between 1k/and 3k, after 3k the car pulls really hard as it should, right now i can't afford a knock sensor replacement, and have all the top engine removed, so would it be too bad if i run the car bypassed for a week or 2 until i get the parts i need to relocate for now? i always use high octane gas btw.


hopefully you guys can help.

i want this car just to get me around my city, maybe 10 miles to 15 miles at most daily, maybe even less, and probably a couple of longer trips, like 290 miles round trip or so twice a month.

[t.mcginley.jr]

How many miles is "high mileage"?

With a high mileage engine, its not uncommon for all of those items to leak... vtc seals, valve cover gaskets, rear main seal, oil pan gasket, etc. A few drops won't mess anything up as long as you check the oil level about once a week and keep it filled up. If there's a puddle under your car (as opposed to a handful of drops) then no its not safe to run it like that.

Oil pressure should be high when you start it, then drop down below 60 when its warm/idling. Its normal for it to go up some when accelerating.

Everyone's opinion on oil is different and it also depends where you live and how you drive the car. Some people use 5w-30 (if it gets cold where you live), some people use 10w-40 (if it's generally warm where you are). I go in the middle and run 10w-30. As for brands, everyone has their own favorite as well. Many people (myself included) like Mobil 1. Others like Amsoil and Royal Purple, etc. However, everyone agrees that full synthetic is best. As for those stop leak oil additives, most people stay away from them and choose to repair the problem itself. Some people are daring enough to run them. I don't trust any of them.

As for the lack of power between 1k and 3k, it could be the KS, but could also be a number of other things like a bad TPS. Check the ecu for codes, if you get a code 34 (knock sensor) then that could be your issue. You can actually get OEM Nissan ones on ebay for about $50. You could do the bypass temporarily until you have cash, just don't run it hard. You should probably do the KS relocation tho as it will save you trouble in the future.

[aroche25]

t.mcginley.jr pretty much nailed it. I would first start by seeing if you have any codes for the knock sensor or other sensors. This is how you do it http://www.nicoclub.com/archives/nissan ... ostic.html.

[johnshop]

Well I like in Texas and is hot pretty much year round so I will go with 40w .

And about the ks I'm almost certain is that. The old owner did relocate but some how the sub harnes is all messed up and even missing one of the cables. So I am 99 percent sure is the ks.

Would 40w slow down the leak right ? Since is much thicker ?

Oh the mileage is 186xxx

Oh and I tried running my codes twice already but is not showing up. BTW when the car is cold is pulls fine when it gets to temp happens