Nissan 300zx Problem

[Rastadori]

So this occurred just now and I'm quite the noob when it comes to mechanics and I really don't know where to start.

So I was driving back home and as I was driving, my car just shut off completely. I was going about 75mph on the freeway and it shut off. I'm not sure why.

I had to pull off, then when i tried to turn it on, it would just keep turning but would never turn on.

Here's some details about the car, the car never had check engine until 3 days ago. I figured out that there was the sensor in the front of the engine, i unplugged it and cleaned it out then engine gone for 3 days. the connection im talking about looks like this




So the car was fine, ran fine before those 3 days and after I cleaned it, it ran fine again until now. Check engine came back up, however, not sure if its that sensor.


One thing I do know, is that i have super old spark plugs. but im not sure if thats the reason for the call to fully turn off and not come back on.

Any ideas? im sorry if its is quite vague but please try to bear with me as im still new to the 300zx stuff.

[spiffy]

That sensor is the coolant temp sensor, even it's broken the car should still run(but not optimal).
If it cranks but isn't firing you are either missing fuel or spark. Checking for spark is easy, unscrew the coilpack and sparkplug, put the plug into the coilpack and ground the tip of the sparkplug against the plenum or something, have someone crank it while you check to see if the plug is firing.

Checking for fuel you can start by listening for your fuelpump turning on when you turn on the ignition, you can also check for fuel smell through the sparkplug hole when it's unscrewed.

Have you checked for fault codes? the ecu has a self diagnosis mode : http://z32.wikispaces.com/ECU+Diagnostics

[Rastadori]

Thanks for the quick reply. I will check on it and get back to you to make sure its nothing serious. the engine alone has 210k miles already. thkinking about just swapping it out for another new N/A

[Rastadori]

Okay just went to do read the code. One thing, when i turned it on, it smelled like gas and my gas gauge wont read my gas right, it says empty but i filled it. anyway, i ran it and got code 13. according to this, its

13*: engine coolant temp. sensor circuit

any suggestions what i should do from here? is it an easy replacement? i dont know any z mechanics that are fair priced in the bay area

[spiffy]

Turned it on as in it started or did you mean you turned on the ignition? Did you hear the fuel pump running?

The temp sensor is easily replaced, just unscrew it and swap, coolant will probably come out when you unscrew it so either let the coolant level down by draining some of it(drain screw is on bottom of radiator) or don't bother and try to to do it as fast as you can, but since you don't have the timing belt covers on I wouldn't recommend it as you don't want coolant on the rubber belt.

Temp sensors are easily tested if you have access to a multimeter to check resistance, a thermometer and a pan to boil some water. check the service manual for testing procedure.

Have you checked for spark and how does your sparkplugs look like? The broken tempsensor might have caused your car to run overly rich and thus fouling your plugs to the point they don't spark. These cars work best with iridium or platinum plugs, denso or ngk brand.

Also mileage isn't a problem if it's been maintained properly, these engines can go really far but as with everything if you don't maintain it it will let you down.

[Rastadori]

Sorry meant to say, the car would crank but would not start. Would have to give it a few minutes and then it would start. So that is why I was assuming if it was spark plugs. I can't hear the fuel pump so that could also be an issue.

I'll check the sparkplugs and see how that goes, as well as drain all the radiator fluid and replace it since it all looks brown in there now.

I got the car at 198k so its hard to say, seems like the last owner had no love for it.

[nissanfreak12]

The one you circles is actually the sensor for the gauge, the one to the left is the CTS.

Make sure when you messed with the CTS you didn't unplug or loosened the Crank Angle Sensor which is the silver round thing to the right of the CTS.

Agreed with Spiffy except you do not need iridium plugs, just use the ones designed for this engine

https://conceptzperformance.com/nissan- ... p_2594.php

Auto part store one are actually a little longer or shorter, I cannot remember which one which could cause detonation, pre-ignition. Since You are running a TT this is even more crucial, NA's not so much. Make sure you also get the correct heat range for the setup you have.

[Rastadori]

Oh the picture i posted was a sample. My car is NA

Yes I'm sure i have to deal spark plugs, that sensor and something with the fuel. those 3 seem to be my issues at the moment. what spark plugs do you recommend for the N/A? should I do a full tune up as well with cables and everything?

[rmlamp]

My 300 had the same problem, it wouldn't start when it was warm, it also threw a code 13. Your CTS is bad and you need to replace it. What happens is, the ECU gets the incorrect engine temperature. When you go back to restart it, the computer thinks the engine is cold and dumps more fuel in for a cold start up. When the engine is warm, you can crank and crank but it won't start until to cools down. They're around 25 bucks from a parts store. And replacing it takes 3 minutes, as someone said, the CTS is the sensor to the left of the one you have circled. Don't worry about draining any coolant, just leave the radiator cap on and you won't lose any. For plugs, go with NGK platinum.

[Rastadori]

Thanks so much for your help. Going to buy the sensor right now and let you know how it goes. Thanks again!

[Rastadori]

So I did the work on the sensor. bought a new one. and walah. Engine light gone. However, a new problem came up. The car sounded fine, turned on fine. and no light came up. It was smooth when I drove it until I started to rev it a little higher on the freeway. The car was warm already but anytime id hit like 3000 and up RPM the car would basically stall but not completely turn off. everything would drop to 0 and like, it barely gets a grip and comes back on. it doesnt sound healthy for the car to move back and forward while driving lol. It felt like a legit stall. Not sure if the sensor or the wiring to the sensor. Or maybe something with Fuel? Since I am aware that my gauge doesnt read my gas appropriately but I do know there was gas in there. What do you guys think?

[rmlamp]

Is it auto? Check for codes again, the check engine light doesn't always come on.

[Rastadori]

It's 5 speed NA. 1990. And yeah it didnt throw no check engine light. I'll recheck to see if it throws anything but as of right now, it did nothing.

Just drove it as well, around 3rd gear at 3000 rpm the car just stalled out. had to pull over and turn it back on. it came back on easily and still no light.

[rmlamp]

I'd start by doing a general tune up. Get the spark plugs replaced, new air filter (if needed), clean the throttle bodies and the mass air flow sensor, check for codes, run diagnostics on the O2 sensors (there's several threads on how to do this) and run a good injector cleaner through. On a side note, do you have the old style PTU, that can cause similar problems.

[Rastadori]

Please excuse my lack of knowledge. never done mass air flow sensor check, 02 sensor check (ill check the threads for this). and not sure what good injector cleaner to use. Also, sorry but not sure what PTU is :/

as for the rest. Ill check the filters right now and see how the spark plugs are. You think I may need the new coil packs or how to check if I may need them?

[rmlamp]

For the MAF, you don't need to do anything other than disconnect it and spray some MAF cleaner on the inside of it, CRC makes a good one, you can pick up at any store. Check out a YouTube video if you need some more guidance.

Pull the intakes off the throttle bodies and spray the butterfly valves down with throttle body cleaner and wipe them down, they should be nice and clean. It'll take a second for the car to restart after this process.

The PTU is the Power transistor unit, it was a recall for the 1990 300zx models. If you have the old one, Nissan should replace it for free, do some research on the forum, there's lots of threads about it and the symptoms of a bad one. Also how to identify if you have the old style or new style.

The best injector cleaner out there is BG 44K, its kind of hard to find and is fairly pricey ($25.00), other good ones are Lucas, Royal Purple and Techron.

Coil packs can be tested with a multi meter, there should be a thread around here that will walk you through the steps on how to do this. If the plugs look bad, just replace them, its not that expensive and its easy, don't forget the anti-seize.

[Rastadori]

Okay. called up nissan. Sadly, they wont do it for me. My vin number didnt even appear on their file. Interesting. I did some research on PTU and the symptombs of a bad one. I'm really thinking thats my issue as of right now. For now the car is sitting until the weekend when I have time, but by then id like to know, how do I test if its the PTU? with a multimeter on to something or what? I'd like to know for sure if thats the problem. Thanks for your patience with me. This is the first time im actually excited to get my hands dirty to fix up my own vehicle. Glad we took care of the sensor. now on to this

[spiffy]

Might be a fueling issue,

do a fuel pressure check:

http://www.300zx-twinturbo.com/cgi-bin/ ... &slide=185

the ptu test is here:

http://www.300zx-twinturbo.com/cgi-bin/ ... &slide=179

and please check/replace your sparkplugs, airfilter and maybe even your fuel filter. Like the other guy say, a proper tune up.
It's no good trying to diagnose an engine that maybe wasn't running to good in the first place.

[Rastadori]

So I kept driving the car slowly to see if I saw any new signs. After that the car completely turned off. Not even the lights on the dash would display. One of the fuses was burn by the battery. I changed it but just as I was about to turn it on. It would burn up again. So there was bad wiring somewhere. Ended searching around and found out the reasoning to this big problem with stalling in the middle. My starter had gone bad and causing my fuse to burn up as well. Changed it up and put a new fuse. so far i have reved it to 4500 when warm and no hiccups or trying to shut off on me. Just thought id report back if anyone ever has this issue, something to look forward to.

Now that this is done, I have a question. I cant get rid of the ticking noise. Sounds like its mostly coming from the right side of the engine only. My question is, does this stuff work?

https://www.z1motorsports.com/engine-pa ... -2476.html

I heard good things about it but it says for TT? Mine is NA and was wanting to try this out. Was wondering you guys opinion? Going to do a tune up this weekend most likely just to get my car in a much better shape.

[evildky]

Lifter tick on these is a real pita, sometimes driving the car hard and revving high under load is what it takes to raise the pressure enough to push out that last bit of air.

[z.Leinbach]

I had some top end rattle for a long time tried all different types and weights of oil and some made it less noticeable, others made it louder, well yesterday I hicked off with some old bottles of 15w50 mobile 1 from work and changed it.. well it must certainly made it quiet, if your average temp ranges are normal to insane, give a 10w40, 15w40, 10w50, or a 15w50 a try to help with noise