Zed Head

Nice find. Good body and a nice paint job. Assume that many small parts will need replacing, like the brake master cylinder (no caps means moisture ingress), and try to save money on the new parts. The nickels and dimes will add up quickly and you'll need to replace more parts than you think. RockAuto.com is a place to spend time on. Here are some links to browse. A lot. http://www.xenonzcar.com/ http://www.nicoclub.com/FSM/280z/

I would get specs. on the clutches and specs. on the engine and see if anything gets eliminated. Then I'd consider how I plan to use the car. If you'll have big tires and want to break the tires loose, use the strongest clutch. If you'll be tooling around the city, only using roll-on power, consider pedal pressure, for driveablity. Some of the high-perf. clutches have a pretty heavy pedal. Also consider that the puck-type clutches generally chatter if your technique is off and can be a pain to drive. I'm thinking Center Force unless you want to drag-race, and forget both of them if you want a comfortable clutch. Maybe a 240 mm stock setup. The Center Force has a heavy pedal, I think.

This is good. You're on the right forum and you picked the right car. I've often thought that the 280Z EFI system is an excellent starting point for learning about cars and EFI. Very basic and fundamental, with excellent documentation in the FSM's. If I was an auto shop teacher, I'd use the 280Z as a teaching aid. Looking back, you might be making a bigger deal out of the starting issue than it really is. This technology is primitive, compared to today's cars. The occasional stuttering start is fairly normal, and as I mentioned, could well be a tank of fuel that the system has trouble with. But, if you want to forge ahead - consider the cold start valve (CSV) as CO mentioned in #42. But look at it both ways, working too well and not working well enough. It's function is to squirt a load of extra fuel in to the intake manifold, to give a fast start. Many of us have removed our CSV's because we're okay with an extra second or two of cranking. But there are times when I realize I could use its benefits (cold day after sitting in the garage for a week or two). By the way, Captain Obvious and SteveJ are the two electrical/electronics gurus on the forum (no offense to any unknown gurus,sorry for the pressure Steve and CO). Consider their electrical words most carefully.

You're kind of at the "think" portion of the typical learning process. Usually starts with Do. Do-think-do-think-do...etc. You have the tools and you're taking measurements but some of them are done using incorrect methods. Working on old EFI can be tough if you haven't had some lessons in basic electrical concepts but it's possible to learn on the job. The two things you're looking at now are voltage and resistance. Voltage is typically measured from a component's electrical contacts to a ground point, which is any metal body or engine part. The battery's negative post is connected to the body and engine, so you're actually measuring the supply of voltage from the battery by this method. Resistance can be measured between any two points and is used to determine either how good the path to the component or to ground is, or to see if a component has the proper resistance for its function (the coil, for example). Sorry to get all teachy, but your methods show some lack. No offense. The more times you run through the do-think cycle the more comfortable you'll be with the troubleshooting process. Even the pros have to stop and think occasionally.

The FSM says that you should see battery voltage at the coil with the key On. You're seeing zero, although it's not clear how you're measuring. There's a diagram in the FSM. You should measure from coil negative to ground. Actually, coil positive to ground would work also. The around 12 volts while cranking is a good number though. You could evaluate spark strength, and fuel injection. Put some of FastWoman's Christmas tree lights on the injectors for injection evaluation. Also described in the FSM. Make sure they're flashing. And check that the spark produced is thick and blue, not thin and weak. There are many other basic meter measurements you can take, coil resistance, for example. These things are all described in the Engine Fuel chapter, and Engine Electrical chapter, in detail. Just saying, if you want to get ahead of the thread. You might have a weak coil, or a weak pickup coil, or just a loose connection, or a dying ignition module. You'll know what's right, what's wrong, and what's marginal.

Actually, a look at your dash voltmeter while starting might show something. They're not super-accurate but a big needle move might be telling. Might also explain why your starter solenoid seems to drop the contact when starting.

I also recently had a battery go bad and do the same. It would turn the engine over for a while, not starting, then slowly lose energy. I put a meter on the battery and found that it was dropping to about 9 (if I remember right) during cranking, then 6 before it was done. I think a reasonable reading during cranking is ~11 or better. If you get a low voltage then there are a many things to look at for that problem.

I'd measure voltage drop at the coil during starting. Both the ECU and the ignition system don't like low voltage. The ECU won't work right, and the ignition system will put out a weak spark. I had a problem with an engine that would only start with starting fluid. The spark was too weak to start the engine, with the voltage drop of the starter motor, but was fine once it started and the ignition system was at full voltage. You've gone full-circle and are repeating things, with the removal of the FPR hose in the video. Electrical is next. It's not as hard as it seems, once you get in and start measuring you'll wonder why you waited so long.

That's for you, not me. Your wiring is not normal. You should understand what's not normal. One screwed up thing can lead to other screwed up things. It could be that your fuel pump actually loses power at Start, because of some unknown wiring or relay problem, and is starting on the residual pressure from when you primed it. I mentioned also, the possibility of a voltage drop when starting causing a weak spark. This is a real thing, and is why car makers have a specific wire bypassing the ballast resistor and turning off everything unnecessary to starting when the key is turned to Start. Measure voltage at the coil when starting, and with the key on. That's a simple test and is a common test for all cars with starting problems. A bad battery, for example, can drop voltage during starting but run the car just fine once the engine starts. A multimeter will be very useful. Do those relay tests. Something will show up. Take good notes, with real numbers.

These are good points. I didn't make a picture of the very well-written relay test procedure from the FSM. It's all there though. 1978 might be the best FSM out there for descriptions and test procedures.

Here's the 1978 fuel pump control scheme. BUT, back to my other point, this scheme does not provide power to the pump by turning the key On/Off as described earlier. In a correct system you should not be able to "prime" the fuel system with the key. So you're studying something that has already been shown to be modified somehow. OR, your oil pressure switch is bad, but this would just give power via two methods, one when the switch is open, and one when the switch is closed. Neither scenario cuts power to the pump. The Start circuit bypasses the control scheme anyway. I see FSM avoidance. It's not as bad as it seems, it's actually very educational and a good read.

Actually, that's not even true. Depends on time-frame. Here's your competition, or what a professional business thinks they're "worth". http://whiteheadperformance.com/product-category/240z-260z-280z-70-78/240z-280z-diff-differential-axles-lsd/

He's probably looking for the big white bottle. Could be that somebody removed it to "clean up" the engine bay.

Put it on eBay with a really high reserve. "Worth" discussions always spin off in to philosophy and personal opinion. And usually end with everybody dissatisfied.

Probably. There's a supply hose from the intake manifold over to the big white bottle on the passenger side fender well area. I've had that hose split also. It's a very small port, kind of like the one on the bottom right in site's picture. My 76 has it more to the left of that spot though. With the engine running, pull the hoses from the bottle and see if there's vacuum.

That last video was informative. Did you "prime" the fuel system like you describe above or just try it with zero fuel pressure? That would make a difference. You're getting closer. Working on these EFI systems is best done by being rigorous, detailed, and repeatable. For example, my question about fuel pressure. Can't tell if the latest video is different from the other ones. Another thing to look at is the TVS (aka TPS). It's the switch on the throttle body that tells the ECU the engine is at idle, so it can add a little fuel. And are you starting with your foot off the gas pedal or are you pressing it? These engines start best with no pressure on the pedal. When the AAR is working correctly. Also, the fact that you can run the fuel pump with the key alone (which you never explained, above) could indicate a wring issue. Maybe your ACC circuit is enabled at Start and the voltage drop is weakening the spark. Could be that the ballast resistor is incorrectly wired, with Start passing through the resistor. Weak spark plus lean mixture = hard starting. Lots of little things to look at, but any one or combination could be a contributor. You didn't get the quick fix so it's time to open up the Engine Fuel chapter and start testing components. Make a list of what's not right and post it (like the fuel pressure issue and the way power is supplied) and somebody might see something. Here's a sample of what you'll find in the FSM.

It's early. I would put more in to your description of "difficult starting". Do you mean that you have to try two times? Or that it idles poorly for 1/2 second? The sputters, before it dies? Because really, it seems to start pretty quickly. How does it start when it's warmed up? Is this only a cold start problem? The more details on the actual problem, the better. If you want to mimic what the AAR would do, open the idle screw up so that when it starts the RPM sit at 1200 RPM, engine cold. You can do this in one shot, the engine won't heat up that fast. Start it, adjust the idle screw, turn it off, restart. See if it starts the way it used to. If it starts fine, but the idle never drops, then it's not a starting issue, it's an AAR issue.

I looked in the FSM and see what you did in your picture and where your hose ends are. Sorry, I couldn't tell what you were doing. My mistake. Haven't looked at AAR connections for a while. All that "bypass" will do is confirm that your AAR was never opening or closing, Not moving at all. All you've done is open the passage permanently. You'll be stuck with an idle that's too low, then gets right, or just right then gets too high. Best to fix the AAR. Sorry for the mess of posts.

Did that hose nipple on the big hose have a plug on it or was it open to air? It should be plugged, I believe. Anyway, I think that your problem is a simple one, don't do anything crazy like adjust the AFM or change timing or what you showed in that picture.

Numbered my edits 3. Actually, I'm not sure what will happen with that setup. Looks like the AAR is directly to air. You'll get a lot of unfiltered air if it's open, might get the high RPM. Or you'll get nothing if it's closed. The loop on the throttle body to the big hose probably has no affect. 2. Moved to front!~ - BUT. Your picture shows that you completely bypassed the throttle blade. The engine might go to sky-high RPM right away. Don't start it like that. 1. Aacck... The AAR can't be bypassed without having the idle speed problems. All cars, even carb'ed cars, have devices to increase idle speed for a minute or two until the combustion chambers get warm enough to work right. Your idle speed with the bypass can either be set to have a very low idle RPM that needs throttle pedal action to stay running, or it can be set with a good cold idle that gets too high after it warms up. If nothing changes though, you'll know the AAR wasn't working.

IF we redefine your issue from "difficulty starting" to "low idle after starting" or "high idle after short warmup" then the problem is most likely the AAR. IT's supposed to be almost completely open at normal cold engine temperatures, like anywhere from 30 - 90 degrees F, then close slowly as it warms up. It actually has an electric heater inside to make sure it closes within a short amount of time. I would pull the hose from the AAR and see where it's at engine cold. If it's closed already, you have a problem. They can be adjusted. Maybe someone messed with yours already.

In the video the RPM went to 1000 after it started and it didn't sound too bad. Doesn't fit your description. It does sound like you might have a starter problem though. It seems to be letting go before the engine starts. Oddly, a 1978 parts car that I had would do the same thing. You had to keep trying until it would catch. The RPM increase with a small vacuum leak is normal. Your fuel pressure readings seem low but it's not clear what you're doing. I don't know why the pump would get power just from turning the key ON/OFF. The pump shouldn't run unless you hit Start, or the engine is actually running. Get the engine running, and take the hose off of the FPR again. Then read the fuel pressure. That will tell you about your fuel pump and FRP. Or take off the small wire from the starter solenoid and turn the key to Start. That will run the pump, but not the starter. One last thing - you said that you confirmed that the AAR flap was moving freely but you didn't say that it was open when cold, and closed when the engine is warmed up. If it doesn't move, then there's no idle speed increase when cold. Basically, it's not doing anything. You can apply 12 volts directly to the two pins if you want to verify it's closing. It only takes about a minute.

You have your "heats" a little blended together and mixed up. Engine heat will show up on your Temperature gauge. If that's correct, then no need for bleeding, or looking for blockages that could cause overheating. The cabin heater just takes a small amount of coolant fromthe back of the head, runs it through a small radiator in the cabin, then sends it back to the water pump. But, as FastWoman said, it's probably your "vacuum **** (rooster)". Here's a link with diagrams and complete explanations of the AC system. My 76 would bust a hose every few months until I patched together some new flexible hose on the ends of the old brittle hose. AC chapter. 76 or 78 is probably the same, if you can't download the complete giant 77 FSM. Start in the engine bay, it's easier than behind the control panel. http://www.nicoclub.com/FSM/280z/

I suggested the gland nut torque just so that you could see the final nail in the coffin. But, if the rest of the tube is in okay shape, the base and the casting could be used for some of the "coilover" kits being sold. So don't throw it away, sell it. Trade it maybe.

That sounds more like a clutch issue. It's not disengaging completely. If you're lucky it just needs adjustment at the pedal. If you're not lucky, one of the hydraulic cylinders is going bad. Start a new thread about the problem. The RTz diff mount just stops the clunking noise that can happen with a loose stock mount.