layz

I just recently bought a 1986 300zx and it runs decent, but after the first day i struggled real hard to start once then was fine the rest of the day. Over the next couple of days it would start rough but then usually be fine. So today after a trip to the dmv i go back to my car and it won't start. I don't know anything about cars, trying to learn though, but i still pop the hood and take a look. All the basic things look okay, ignition coil had blown on my supra(car i had before this) so i checked those wires they all look fine, so I get back in the car and try pumping the gas as i start it. I got it started then went home, started without to much trouble when i took it 5 minutes up the street and played football for a couple hours. I go to start it and head home and it wont start again. I pump the gas several times it won't start, try probably 8-10 times then finally it starts and revs to like 3k cause i'm on the gas, i let go and pump it a couple times around 1k then release the pedal and it dies. Next try it goes to 3k again then i finally get it to idle around 1500, it'll rise slowly to about 1750 then and randomly drop to 1300. I've seen people have problems with fuel relays and other things like that on the forums, any idea if its something like that? I have a friend who knows alot more about cars who i'll have look at it but trying to atleast diagnose the problem tonight or tomorrow.

cliffnotes: 300 zx won't start sometimes, will start others. Pumping gas helps it start. No idea what problem is and don't know to much about cars. Looking for help.

chirp the 1-2

a buddy of mine had a turbo 86 that had some starting problems after it was warmed up and then sat for awhile. He had to replace the fuel press regulator because it had a fuel temp sensor that had gone bad. Might wanna test that if u can. I work at a nissan dealership so if u do figure out what it is i can get the parts cheap!!

HatefulMechanic

check your coolant level. sounds like its either low or you might have a bad CTS, since you said pumping the gas helps.

layz

thanks guys, i'll talk to my friend today and try those things, and let you know what it was, and a deal on parts would be great, really appreciate it

minboostS13

belive it or not that could be a TPS issue. What about the IAC motor, is it functioning? Try to adjust it and see what happens.

Odin

ckeck the fuel pruessure after you shut it of and watch it for about 15 min. if it drops more than like 5 or 6 psi you have a bad fuel pump. It sounds like your losing fuel pruessure as the car sits. That may be why its a little hard to start after sitting and keep running - your fuel pump is trying to re-build the required fuel pruess. to run - and once it does it runs fine

Odin

that drop in pruessure im not exactly ,positive on - you may want to check your vehicles service manual or go to a nissan dealership and ask them to look it up on alldata - they should do it for free

layz

well car still has random starts after doing a tune-up, seems as though cold weather makes it worse, but it'll even start fine once then not start for like 15 minutes an hour or 2 later during same conditions, if anyone knows someone who could take a look at it and identify the problem for cheap (or free ) pm me and let me know, any help is appreciated, just need to figure out what the problem is