FastWoman

We don't know that your ignition module is bad yet! The next time your car quits on you, you need to be armed for testing it: (1) A shot of starter fluid in the intake to see whether the engine will start and run for a few seconds before dying -- would rule out ignition module and redirect your attention to fuel. Or (2) try jumping a spark from a sparkplug wire to ground while you crank the engine -- would also rule out ignition and indicate fuel. Parts are fairly available. You can search by year and model on ebay. I've also seen ignition modules for sale at AutoZone, but I don't know whether they're any good or for real. Finally, you can do what a few of us have done -- an GM HEI ignition module retrofit. I'm happy with mine. But first do the diagnostic work. You don't want to go randomly replacing parts you don't know are bad. Maintenance will cost you quite a lot of money that way.

So I was thinking a while ago about a modification to the fuel rail. The old style of injector insulator has a plastic bottom and metal top, or so I think. What if a different metal top were machined that would have a cooling tube running through it to cool the injector body? The cooling tubes could be plumbed in series with each other. Then return fuel from the FPR could return through the cooling tubes before going back to the tank. If it were put together that way, then priming the pump for a minute or so would actually cool the injectors, so that starting would be possible.

That's the boss for the #6 exhaust rocker pivot. Probably unlikely to leak anything? I would think a good welder could touch that up, even without removing the head. It might not even be necessary if the crack is stable. The big question, though, is whether there's chocolate milk in the crankcase. The engine should definitely get a round of new plugs and wires. That's never a bad thing.

Chicken, I have a priming switch on my Z, and I can tell you it doesn't really help to resolve the hot restart issue. I think the problem is that the cool fuel won't dribble into the injectors just with gravity and therefore won't cool them. Instead, you have a stubborn pocket of fuel vapor inside each injector that doesn't really budge from where it is. The only way to get rid of that pocket is to inject vapor into the intake. Then fresh/cool fuel enters the injector, flashes, and must be injected as a vapor. Eventually this happens enough that the fuel vaporization, combined with cool air rushing through the intake (perhaps a more significant factor), carry away enough heat that the fuel no longer flashes inside the injector. And that's when the engine evens out.

Take heart. She's only unreliable because she's got some part that's acting up. Replace that part, get everything in working order, and drive the car regularly. Then you'll see the Z is a very reliable machine -- especially the fuel injected 280Z. I've found that the Z is a less expensive car to maintain than most modern cars, despite the fact that parts are harder to come by. It's a simpler car, so there's less to go wrong. There's also plenty of space under the hood to do repairs. It's a very good car for a DIY'er. There are a number of us who drive our Z's daily or semi-daily. We usually start out with problems like yours, but eventually our cars get us around pretty reliably. I don't hesitate to take my Z on the road to other cities. It's a great road car! You'll get your car straight.

I'm going to make a few guesses: The hot tunnel: Perhaps your engine is running lean. This can be due to a variety of things. In a 1976, I think the more likely problem would be vacuum leaks. If the vacuum tubing is in bad shape (which it usually is on any old car), the best/easiest thing to do would be to replace it all. You can get new tubing at your local auto parts store. Next, very carefully check the accordian-shaped boot connecting the airflow meter with the throttle body. It may have splits in it, which would result in un-metered air. Lastly, buy a cup of Yotastic yogurt, enjoy the contents, wash out the cup, and do the now famous "yogurt cup test" on your intake, first described this way: For a 1996, I think you would have to pull off a different vacuum hose, perhaps the one going to the fuel pressure regulator. I think you might find that you have a leak between your intake manifold and cylinder head, especially around cylinders 1 and 6. This is a common problem, and the fix is to pull and replace the manifolds (i.e. with a new gasket). That's somewhat labor intensive, of course, so let's hope you don't have that problem. The problem with your car dying in hot weather is likely due to your ignition module or your fuel pump overheating. Once they cool down, everything is OK again. The fix is to replace them. When your engine dies, coast with it in gear, and watch the tachometer. Does it still show a reading, or is it at zero? If it reads zero, you've probably got a bad ignition module. Another test: Buy a can of starter fluid. When your car dies, pull off a small vacuum hose, spray some starter fluid into the intake manifold, replace the hose, and try starting the engine. Does it fire for a second or two? If so, the problem is more likely fuel related, and your ignition is probably OK. And your dad probably showed you the trick about checking for spark: Pull a spark plug wire, perch it very close to a piece of bare metal, crank the engine, and check whether a spark is jumping between the wire and the metal. (You might need to extend the spark plug wire's conductive path a bit by inserting a paperclip.) Check these things immediately after the engine dies, and let us know what you find. We'll help you from there.

Yeah, "tan" isn't a color anyone likes to see. Rather than a "milky" tan, is it perhaps just a clear, light brown? If so, that would just be motor oil. A new valve cover gasket would be cheap and easy. You can also pull the dipstick to check for chocolate milk, but a look under the valve cover would be even better. If you haven't done your first oil change yet, you'd see it in the drain pan also.

Hey, welcome! Another woman! Woohoo! The gas tank whoosh is probably normal if you're getting it in the heat of the afternoon. The gas cap holds pressure. There's a vent (through the carbon canister) that will hold pressure up to a point and then release anything further. Coolant leaking onto a spark plug is strange. The head gasket ("main gasket?") is located beneath the spark plugs, so I wouldn't think it would be the source of coolant leakage onto your spark plug. Perhaps you have a pinhole leak somewhere, and there's a bit of spray. It wouldn't hurt to replace the hoses. It's more likely you have motor oil leaking from your valve cover onto your plug (not a serious issue). Is the liquid green or brown? Is it sweet? The "hot restart" problem is a known and typical issue with the 280Z. There are several theories. Mine is that the early fuel injection designs were meant for different fuel formulations than we have now, and they had issues even then. When you shut off the engine, heat soaks the injectors, which are normally cooled by fuel. When they get hot enough, they vaporize the fuel, and they will only blow vapor into the intake until they cool off -- not enough fuel to fire the cylinder. The problem is made worse with ethanol gasoline (more volatile than old-fashioned gasoline), and it's even made worse by winter blend ethanol gas (which is even more volatile than summer blend, especially if you have it in your tank when you run the car during the summer). The problem is worst if you let the car sit for 20 min. After about another 15 min, the car becomes much more startable. If you're in a rush, you can hurry the process by popping the hood and letting the engine cool. The design problem was partially remedied in subsequent years by: (1) creating webbing between the intake runners to block airflow from the exhaust ('77/'78), (2) shielding around the exhaust -- between exhaust and intake manifolds and around the exhaust manifold ('77/'78, I believe), (3) putting vents in the hood ('77/'78), and (4) eventually providing a cooling fan for the injectors that runs after engine shut-down (280ZX generation). FAIW, these cars are very easy to work on, although a head gasket might be over most people's pay grade. You can download a Nissan factory service manual from the "reference" section of www.xenons30.com. It's one of the best service manuals I've ever seen -- far and away better than a Hayes or Chilton's. It's what the Nissan service departments would use, but Nissan also sold copies to owners for maybe $80. If you prefer paper, like I do, you can probably find a used one on ebay or Amazon. Make sure it's for your year of car.

Hi Redwing! Welcome! Please check your notifications (upper left). I sent you a message. If you start another thread, I'd love to respond to it. Unfortunately this is someone else's conversation about a different issue.

No, it wasn't I who had that issue, but it makes sense. The more concentrated the slurry gets, the more blocked the pickup screen gets. The acid test would be to park the car for 5 min, let the crud settle and fall down from the pickup screen, and then start again. Let idle for a few min to top off the engine temperature, and then try driving. If the engine now performs better (and then gets worse pretty quickly), then a clogging pickup screen might be the problem. Of course nothing beats a peek inside the tank through the view hole or even a look at the gas coming out the drain hole.

Gotta say... My Z keeps losing its pep. I keep tweaking the tune, but the old analog ECU just isn't doin' it. Most people would say it runs great for an antique car, but I know how a Z is supposed to run. Would love to drop in something with 1's and 0's! How's it coming, Len?

Oops... Didn't see page 2 of posts. Yes, your pump is bad! Hurray, you found the problem! Hope it's not too expensive. But at least it's an easy fix. I recommend a Fram G3 filter installed prior to the intake of the pump, so that it won't get jammed up with rust from the tank. I second Chas' recommendation for a Bosch pump -- quiet, efficient, durable. Great equipment.

Something else to think about: Most LED assemblies use (inexpensive) drop resistors for regulating current. After you add up the forward voltage of a stack of LEDs, the head-room from there to the 12-14V system voltage usually is not very much. Then if a voltage regulator fails and starts throwing maybe 16V to the system, the voltage across the drop resistor can increase markedly, resulting in a ton more current and the destruction of the LED assembly. A friend of mine was plagued with these problems with his solar/LED camper. (An overvoltage when under motor took out half of his lighting.) For a few extra pennies, an LED assembly can be actively current-regulated, e.g. with a simple transistor circuit (transistor, zener diode, a couple of resistors), virtually eliminating death from overvoltage. I would hope (!!) that for $250 per unit, you'd get the few pennies of additional parts to make the thing bullet proof. On the other hand, the only actively regulated LED circuits I've ever seen were turned out by a quirky little business in Fiji that catered to boaters -- Bebi Electronics (http://bebi-electronics.com/), now forced out of business because of a decaying political situation. So be aware that an overvoltage can probably blow these things out!

Maybe you still have some water in the system?

Ah, a ZX head! OK, that makes sense. The intake seems to be '77/78, judging from the manifold vacuum ports and EGR. EFI is probably '77/78. Yes, wiring in the translocated CTS should be an easy job.

Download the factory service manual! Look on page EF-14. The big, 2-wire gizmo is the thermotime switch. The smaller 2-wire gizmo is the CTS for the EFI. The 1-wire gizmo is the temp sensor for the gauge in the dashboard. This page: http://xenons30.com/reference.html This file: http://xenons30.com/files/FSM/1978%20280z%20FSM.zip Also this file: http://xenons30.com/files/280zfuelinjectionbook.pdf I believe the sensor near the starter would be for oil pressure, but I suppose it could be for oil temperature (a modification someone made). It's not stock.

From the schematic, I think you're looking for two black wires (approx 16 ga) with itsy bitsy white numbers printed on them every few inches. One of them will have the number 13, and the other will be 49. The #49 wire goes to ground, and the #13 wire goes to pin 13 on the ECU. You'll need to install a Bosch-style connector on those two wires. You can order them from Ebay ("280Z injector connectors"). As far as I'm aware, the polarity of your connection doesn't matter. If I were you, I would order all the connectors you need to do a complete connector refresh -- at least the 2 pin connectors. It will make your engine much more reliable.

I usually don't have hot restart issues, but it happened today. While I was out on errands and let the car sit for maybe 15 min, the engine fired up, died, fired up again, and ran roughly for several minutes. The car had been sitting for several months and had a full tank of winter blend gasoline. Today wasn't especially hot, but I guess it was hot enough. Reminder: All stock '78 with FJ3 injectors, fuel pump priming switch, and light insulation on the fuel rail.

IMO there's nothing like the Bosch replacement. I've read of too much trouble with aftermarket pumps. And yes, the fuel flows right through the motor to cool it, so there is potential for it getting rusted/stuck. Nice idea about trying to budge the thing with reverse polarity!

DingDingDing! Yep, that would do it! Fix that, and get the AFM back to spec. I suspect your engine will be quite a bit closer to the mark. It may still need some work after that, of course. We'll be here to help. PS I meant to say that "Yotastic" is a yogurt cup that will work. I think Yoplait is too skinny to fit. (Of course you can use any plastic cup that will stuff snugly into the rubber boot.)

I wouldn't tap on the fuel pump. You can crack a permanent magnet. If it's really jammed up, I THINK you can disassemble and clean.

My guess is that for it to run right only when you tighten the living @#$% out of the AFM clock spring, you've probably got an open coolant temp sensor circuit. Normally when that sensor opens up, the engine will belch black smoke out the tailpipe. I wouldn't expect the engine to run as well with all the emissions stuff deleted, but I also wouldn't expect it to have this magnitude of problem. IMO, the best thing you can do is to download the factory service manual and the "fuel injection bible" (both free at xenons30.com). Work your way systematically through every single part of the EFI system: Start by replacing every bit of old vacuum line you may have left, if any. Make certain it's connected properly. Do what I call the "yogurt cup test" (search it) to verify your intake is tight. (Yoplait works best.) Fix/address any leaks. This often involves replacing the intake/exhaust manifold gasket (a joyful experience). Clean and lightly lube (with silicone dielectric grease) every electrical connection in the EFI. Verify that every part is functional and measures to spec. Verify that every part is connected correctly (e.g. wiring). Set your AFM back to spec spring tension. Look for the "beer can" method on Atlantic Z. Carefully verify that the internals of your AFM aren't messed up. Clean the potentiometer trace. Put 12V across the thing as instructed in the FSM. Then with an analog volt meter, measure the voltage at the wiper as you open the vane. It should vary smoothly and not jump. Measure/verify EVERTHING from the connector to the ECU as a final check. Verify that your FPR is really regulating at 36.4 (?) psi with the vacuum line disconnected. Your engine should be able to idle now, so let's work on timing: Check that your distributor breaker plate rotates freely under spring tension and that your vacuum advance works. Disconnect and plug the vacuum line. Set your timing to 10 - 13 deg BTDC. Reconnect the vacuum line. Put a vacuum gauge on the intake manifold. You should ideally have a vacuum of 18-19 in Hg, but probably have somewhat lower. Once you get to this point, we can help you to tweak your fuel/air mixture to get this higher vacuum. Somewhere along the way, you should also adjust your valve lash. This will help, but it's quite unlikely to be the problem.There's a 12 step program for you. Along the way, you will consume both yogurt and beer, which don't mix too well. Good luck!

Try putting a volt meter on your pump. See if +12 is making it to the pump. Also check the integrity of your ground. I believe the ground wire runs from the pump, through a grommet, and into the toolbox area, where there's a ground screw. (I'm not certain about this.) Also try hot-wiring the pump to force it to run. This will rule out a bad pump. If you're not getting +12 to the pump, check the two big connectors just inside the firewall on the passenger side. In the corner of one of them is the fuel pump wire. I think it's blue with a green stripe, or maybe green with a blue stripe. See if that connection looks good. (That connection had gone bad on my car, and I think the contact is undersized for the electrical load.) Check your relays. You have both a fuel pump control relay and a fuel pump relay.

Or the power to the accessory air control valve or thermotime switch. Or the power to the injector drop resistor assembly beneath the master cylinder.

When you turn the key to "start," you can run the fuel pump for up to 5 sec. It sounds like when you let the key return to "ON" or "IGN," your pump might not continue to receive power. It may run just a few sec on the fuel pumped when you were cranking the engine. Ordinarily, the fuel pump is designed to shut down when the engine stops running (a safety feature). The strategy for detecting a non-running engine changed throughout the years. If your '77 is designed like my '78, this shut-down occurs when there is neither alternator output nor oil pressure. Either alternator output or oil pressure will enable the fuel pump relay. But check the FSM for your year to make sure. To get from point A to point B, you could "hot-wire" your pump. Run a wire from the + post of the pump to the battery, and it should whir away, enough to get you home to a location where you can take your time debugging the issue. But be warned: If you get into an accident, and if the integrity of your fuel system is compromised, your fuel pump could spray fuel all over the place, and you could die in a ball of flames, along with everyone around you. The safest route is just to have the car towed. Or perhaps you're on good enough terms with your ex that you can take your time debugging the problem where the car sits now.