l28manzz

I have a stock '77 280z and I have been away at school and have not been able to start it very often. Every time in the past when I have tried to start it, it has worked, but this time it did not want to start because if some electrical issue. I have power when the key is at the accessory position but when I turn the key to the ON position, I hear the relays click and loose all power, but I still have 12 volts to the coil. When it is cranking, I can hear the fuel pump running but it doesn't start. I have checked all of my electrical connections but am at a loss on what could be causing this. Possibly the keyed switch? I'm not sure. Any help would be appreciated.

theramz

Maybe clogged fuel filter from sitting too long and bad gas. Check for spark at the plugs and fuel pressure (35 psi)

l28manzz

I hooked up a fuel pressure gauge and I have 36 pounds pf pressure between the filter and injectors, and I put fuel stabilizer in the tank last time it started. I am sure it is an electrical problem because I loose all power when the key is on.

beg3yrs

How can you lose all power in the on position when you hear the relays click and you have 12 volts on the coil? To me losing all power means you've got absolutely nothing. What power has gone away in the On position?

l28manzz

It is a really weird problem. I should specify though that from what I can tell, I loose all dash power and all engine power except to the coil. I am starting to think that the ignition switch is bad and I will hopefully be testing that later today. Regarding the relays, when I turn the key to the accessory position, they click on, but when I turn it to the ON position, the relays click back off, and the e-brake light, charge light, seat belt buzzer, and all gauges turn off.

zxguy1986

Yeah, probably the switch. I replaced the ignition switch in both my '86s. That switch is trying to do a lot and just gets tired. Contacts wear and don't work right. I recall that they were available aftermarket and were not expensive. Given all the previous owners and the fact that no two people turn a key the same way, the switch is worn out. Nothing too fussy in the replacement either. You can probably do it yourself in an hour. Only problem: you get a new ignition key that only works the ignition.

beg3yrs

IIRC, the switch itself is independent of the key cylinder in the 240, 260 and 280Z. May be different in the ZX though.

1977 NISSAN 280Z 2.8L L6 Ignition Starter Switch | RockAuto

l28manzz

I checked the ignition switch and it is good at all key positions. I was hoping that was going to be the problem because that is an easy fix. I am still at a loss on the problem.