Zed Head

The gas cap is only supposed to let air in as gas is used. The vent for the tank, to relieve pressure, is supposed to run through a hose up to a charcoal canister in the engine bay. People sometimes remove them as "emissions junk" not knowing what they're doing. That might the cause of the pressure buildup. Maybe somebody removed the engine bay vent and was using a vented cap in its place. Shouldn't affect your gas gauge though. It's just a metal float on a lever that moves up and down with fuel level. Floats, in general, do sink sometimes, although I've never heard of the gas gauge float doing that.

Did you mean no clicking? That's one thing, that indicates the injector solenoid is moving the injector pintle. Whether good fuel squirts when that happens is another thing. The key to troubleshooting the EFI system is to isolate the various actions that are supposed to happen. Sounds like you've done that with the ECU grounding process, which also confirms the signal from the coil negative terminal. If "pulsing" means the noid light flashed as the engine turned over. One of the hardest things about talking on the forums is describing what's happening. p.s. the ECU is grounded through its own pins in the harness. It doesn't need the ECU case grounded. But that does bring up the other end of the power circuit - the ground point for the EFI harness. Sometimes people have problems if that connection is dirty or broken. You can check the ground at the ECU connector also, the pin numbers are on the diagram.

Could be they were just fouled. Four of them worked. Once they foul and misfire a few times, the carbon paths get baked on, and you're kind of cooked unless you clean them or replace them. Might not be the type or quality of plug at all. I've wasted lots of troubleshooting time myself, in the past, when a simple tuneup, with new plugs, ended up fixing the problem.

There's room in a Mustang for the Nissan L6. The turbo engines can make a lot of power.

Here's another one showing all kinds of machinations in order to squirt solvent through an injector the same way that hundreds of gallons of the very powerful solvent gasoline have already passed. Not suggesting that you clean them this way just that you can open them with a battery. At 4 minutes. Incredible how much wrongness a person can ft in to six minutes. Edit - you can watch injector-testing videos for hours. Very entertaining. The best ones probably burned up though.

Here's a decent video showing how to use a 9 volt battery to open an injector. The relevant stuff starts at about 1 minute. Beware sparks. These videos are scary.

I think that you might not be understanding how the injectors work. They open when current flows through them. The ECU creates a grounding point, allowing current to flow. When you grounded the circuit yourself, at the ECU connector, you took the ECU out of the picture as the cause of the problem. The ECU is at the end of the circuit. Your train of thought might be stuck on its track. I mentioned the above before but you haven't acknowledged it and you've repeated the same error in understanding. No offense intended, but it's clear. You also aren't giving the information on which pins you used to ground the circuit at the connector, just to show you used the right pins. With the power of your battery, your Fluke to confirm power, and some lengths of wire (or an old EV1 plug, the connector), you can test the injectors directly at their spot in the manifold. You might try that. You'll need to do it anyway, even if you remove them or buy new injectors.

It seems to be something someone added on. I don't think that Nissan used that kind of switch knob either. I got the pictures from the Owners Manual. http://www.xenonzcar.com/s30/ownersmanuals.html p.s. You should fix your "Z". It's not an N.

I bet you could take it a CA or Texas car meet and get 50% more. Otherwise, there's this.

Might be the power antenna control. What year? A picture would be great. Edit - of the car and switch.

Check this out. https://www.ngk.com/Automotive-NGK-l1411.aspx

Glad you figured it out. You should have been able to reset the gap to about .030" and got consistent spark. If it was "-10" at the end that means that it's designed for about .040" gap and they come preset that way. The "R" means resistor and they do go bad sometimes, apparently. If it was a bad plug you'd see it by measuring resistance from the top to the center electrode. You could do that for fun if you have a meter handy. Edit - just noticed that there's nothing in Blue's NGK fake link about China. But there might some subtle anti-Semitism. Not saying Blue is, just saying it's in the link. Also, odd that there are no links back to the NGK home page so that you can verify where it originated. Rabbit hole, gopher hole, who knows. These conversations all end up in a bad place, inherently.

I edited that other forum thread and it will probably be disappeared. You're supposed to a donating member to sell things on that forum. If he's muttering $500-800 then it's not free and he's not going to junk it. Post his craigslist ad when he puts it together or you get a firm price. He's your friend, but it looks like moving the car will be a hassle, just due to indecisiveness. It would be a real bummer to rent a trailer and show up for your free car then be held hostage for a cash ransom. No offense. It has probably sat so long because he thought it had value and now that he's confirmed that it does it will probably sit another 8 years. Nice try though, and thanks.

Zero views so far but most people get on after work. Somebody will grab it for sure. http://forums.hybridz.org/topic/127272-free-1981-280zx-turbo-car-intact-with-engine-in-paradise-ca-you-haul/#entry1189638

When you grounded the injector pin at the ECU connector you did the job that the ECU would do. So the status of the ECU is unclear. I've had stuck injectors, in my hand, with battery voltage applied, and tapped them with a screwdriver and heard them free up and click. So they do get stuck, but come loose. From the same old engine I had injectors that were stuck and would not come unstuck. So they do get permanently stuck too. If the fuel system was open to the atmosphere diffusion will carry any moisture and oxygen through the lines to the injectors. I've read accounts from a forum back when they were called bulletin boards or usenet or whatever,about sticking an injector just be getting a drop of water on the pintle. Water is bad. If you live near a wrecking yard you might find an old car with EV1 style injectors and buy a couple just for experimentation. If the gas in the fuel line still smells like gas they'd probably be fine. You can even take a 9 volt battery in to the yard to test them before buying. Then you'll have known good injectors to test the system with.

Some us here frequent several other Z-based forums. That car would go quickly if you posted over on hybridz.org. I can post a link over there back to this site. I'll do that if you don't reply here in the next 20 minutes. "Free 1981 280ZX Turbo car, intact, with engine, in Paradise, CA. You haul" should do it.

I think that the gear is just a press fit on the shaft. Yours look like it might have moved, there's a colored spot on the shaft. Also looks like it might be bronze or some other non-iron based metal alloy. I don't know what the stock gears are made from but maybe yours is aftermarket? And not as durable as Nissan stock. I always wonder when people worry about debris making it to the bearings. That oil is supposed to be filtered, so only material smaller than the filter limit would make it, or if the filter clogged and the bypass opened up. Just saying. Cut open the filter and you might find the rest of the gear, in oily dust form.

That's a good point. Funny that we have those 6 potential short circuits sitting there all the time, with the crappy typically burnt crispy connectors the only thing stopping it from happening. I don't get too far in to the fine details of of a problem until I know that the measurement techniques are right. I suspect that DC8 is early on the learning curve, but making rapid progress. You're the one that pointed out to me that if the other injectors are connected, you'll see voltage on both pins of the disconnected one you're testing, because there are parallel circuits. So if all are disconnected you see only one pin voltage but if others are connected you'll see voltage on both. I think that still applies even without dropping resistors. The wiring diagram implies only one grounding transistor though, but all six terminate there. Kind of interesting.

Check your local yards and craigslist for manifolds. I took my first one to a shop to have a stud removed and have it ground and the guy charged me the very top of his estimate,even though I told him if it didn't look like it was going to come out to just stop. He looked at it and said it wouldn't be a problem and should cost at the low end. He seemed sincere. I think that he just enjoyed the challenge of removing it, at my expense, when it turned out difficult. My fault for not resetting the upper end of the estimate, but I found junk yard manifolds later that I could have bought and used right away for 1/3 of what I ended up paying.

Don't forget, Kansas is way out there. You can't ask big coastal-city money when you live in the country. No offense kacrow.

When you grounded them at the ECU connector you took the ECU out of the picture. So you can't determine if the ECU is good or not. But you could say that even a good ECU won't open the injectors. How did you do the grounding? And which pins did you use on the connector? And was the key On? Did you measure battery voltage at the pin before you grounded it? No offense, but you might be missing something. Not enough detail to tell if you did it right. You can also power each injector individually. Some people use a 9 volt battery because they're afraid that a full twelve will damage the injector. But a short tap or two with full power won't hurt them. It's the extended current that causes the damaging heat. A tap or two with a full twelve volts might be enough to pop them open. It might get you running but they might not be balanced if they've all been stuck. Kind of odd that you don't get at least one click.

It's described in the FSM. The ECU uses spark counting to know the crankshaft has turned. It's a revolution sensor but not an angle sensor. As noted earlier, your car doesn't have a CAS if it's NA.

I've seen it proposed but haven't actually seen it - bad grounding of the spark plug body and threads to the head. Several ways to test it or fix it, from vigorous cleaning of the threads to running a dedicated ground wire from the plug body to ground, or jamming a screwdriver between the plug and head. You get the idea. Seems far-fetched but fits the symptoms.

Another test for the injection system is to connect a lead to the coil's negative post. Let the other end hang free, turn the key On then tap the free end of the lead to ground to create a spark. Every third tap should cause all six injectors to click. That test works all of the parts, including the ECU. It provides a stronger spark though because the starter motor is not engaged. If you sit down and think things through and collect all of these various suggestions, you can come up with a systematic plan to test parts, in addition to the factory tests. You're talking about taking the injectors out but you haven't test their functioning yet. You can also ground each injector at the ECU connector, with the key On, mimicking the ECU's function. Then you'll know if they're stuck. Lots of little tricks out here.

I would try starting fluid, with a squirt of oil in each cylinder, before going too far, just to be sure it's an injection problem. If you didn't flush the lines to the injectors you might be squirting old dead fuel or water in to the cylinders. The injectors also tend to get stuck closed if the fuel in them dries out. I've freed them up by tapping with a screwdriver. There are many other possibilities for not firing or not injecting. You have to work your way through them. Using starting fluid is a good way to test many things at once. Timing, spark, compression, etc. A friend and I spent hours trying to get an old 1963 Bonneville to start that had only been sitting one year. A farmer cruised by on his tractor and told us to squirt some oil in the cylinders. We did and it fired right up. The rings were dry and it just wasn't compressing the fuel-air mix. I've also had an engine that had spark but it was weak. It would only start with starting fluid until I changed the ignition module. Your ZX module could have bad grounding and produce a weak visible spark, not strong enough to kick off old fuel in dead dry cylinders. Could be a combination of weaknesses.