Hi everyone, this is my second time posting, last time I had a faulty differential, got that fixed and fell In love with this 84 turbo Z... but yesterday as I was waiting for the car to warm up it died. Gauge lights were still on but the car wouldn't start back up, waited a whole day and tried again this morning, still nothing.

*Removed fuel hose and got no fuel pressure while cranking, wired pump to battery and it worked just fine.
*I took out spark plug #1 and cranked, no spark. My volt meter read voltage going into the cap and rotor (which are New) but no spark from the boots..
* checked the fuses in the driver kick panel and all look good.

What should I do or check next? Any help is greatly appreciated

 

Checked ECU and both green and red light are on. Double checked the fuses and they are all good, even tested the fuel pump relay and that works.

What other relay should I check?

 

I checked the relays above the driver kick panel fuses and all were in working order, but once I put everything back in place I herd the fuel pump kick in and it started right up. I turned it off and the fuel pump did not enage when i tried again.

I jigled the keys from the on and off repeatedly without cranking until I herd the fuel pump engage again then it started.... maybe its an ignition switch issue.

(Reaponding to my own post just incase someone is having the same headache I am haha )

 

Well, you picked up on something good. If that ignition switch is original, it definitely should be replaced. A worn out or bad one can cause all sorts of problems. Do that before anything else.

You don't say how long you have owned the Z but it sounds like you need to catch up on all the regular maintenance the prev owner skipped. It takes time and patience but is worth all that. That Z intends to run well every day if you let it.

You have the factory service manual from Xenon? XenonZ31 Reference If the site doesn't work yet, let me know and I can email you a copy of the '84 FSM. It's loaded with testing and troubleshooting pages that are easy to follow. One at a time and you cover just about everything.

When you get it running, run the computer diagnostic right and see if it tells you anything you don't know or didn't expect. Keep up the good work!

 

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. Usually on a rainy night around Oh Dark Thirty.

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. DON'T USE DIELECTRIC GREASE.

that some stuff to get you started. go to courtesy nissan and buy the fsm disc. xenon31 site apparently dead for fsm anymore. Read up on stuff.

the ecu diagnostic test is usually useless.

 

search the web. nico club maybe has fsm for free download.

 

The FSMs and other reference material from the XenonZ31 page have been relocated to:

XenonZcar.com Z31 1984-1989 300zx Reference

 

I have checked everything, and after testing the relays it started again. but after running it for a couple days and doing a tune up, new NGK spark plugs... I ran out of gas (fuel gauge doesn't work) I added a couple gallons and I attempted to crank it over again when I filled it up but it would not start and now a new problem has arisen. It keeps blowing fuel pump fuses

 

Blows them when I put the keys in the ON position, I've disconnected the blue connector that goes to the pump and then put the keys in the ON position and it did not blow the fuse. I'm thinking there's a short in the pump itself? What else could I check.

 

was not able to find the short on the fuel pump but I rewired it and now it engages when put into the ON position and does not blow fuses. Now I'm not getting spark agin... battery and battery terminals are clean and corrosion free. All sensors, relays and connectors are in good conditions but still doesn't start. I'm definetly regreting buying this car.

 

Wondering, what did you actually do about this?

 

turns out it was a short on the actual fuel pump wires. I still have no explanation as to the intermittent ignition issue. I haven't had an issue since