Zed Head

Purist. http://www.speedhunters.com/2018/01/the-purists-fairlady-z/

Does the tachometer behave normally? Smooth, seems to correctly match RPM? The tach needle is a clue to ignition problems.

The author is listening, via Comments. Maybe somebody can let him down gently. Here's an ironic one, from "researchisyourfriend". I saw the user name and thought he was going to give a lesson. Disappointed.

I explained earlier how a bad ignition module can make it run rich. Too many sparks. It could also cause rev limiting. Overheating. You said that you've tried both AFM's and both ECU's. The distributor is simpler than it seems. A six-spoked metal wheel that has teeth that pass by a magnet. Check the air gap, the resistance of the pickup coil, look for kinked or broken wires. You've kind of worn out the ECU's and AFM's. Ignition will seem like a vacation. Edit - could also be two bad ECU's. Running rich and sudden dying are two signs of a bad ECU.

If somebody adjusted the vane spring on your AFM it could be going full open at low air flow. 246 supplied a re-calibration procedure in the atlanticz.ca link. Out of adjustment AFM fits what you're describing, at least the rich part. Are you sure that nothing is blocking the air path? Air is what allows the engine to rev. Is your throttle body blade opening completely? No rags in the intake ports or intake manifold? If everything is right mechanically it should rev high easily with no load. Try removing the oil filler cap and some vacuum lines and see what happens. Let some air in to blend with all of that fuel.

CZCC.com has the FSM"s here also. 1976 is very close to 77 if you just want to download a chapter instead of the whole book. http://www.classiczcars.com/files/category/13-280z/ The Floor Heat warning is just a sensor over the catalytic converter area, and relay. Probably comes on when the key is on but engine not running to verify that the lamp is good, like the Brake Check lamp does. You said "turned it over". That means Start. Did you check for power with the key ON. Check for power at the coil, and at an injector plug or two. Those are out at the ends of the circuit and will tell you if the relays are working, to a point anyway. You can learn a lot with the key On, and a meter check at a variety of spots.

Check the dimensions against the specs. in this link - https://www.opticatonline.com/part/moog-driveline-products-393-universal-joint Looks like 56mm from outer groove edge to outer groove edge. Maybe you got the right box/wrong product.

Do you have any documentation? A build sheet? Provenance? 1/4 mile time slips? Would make it more interesting. @ABQ240

Sorry, that was pretty negative. What do those SpeedHunter guys do anyway? There are several cars owned by members of this forum that would be ten times better to write about. The period correct thing got me...

Interesting car but the writer started with a theme that didn't fit and just kept writing to the theme instead of the car, didn't he? I don't know what a Japanese Fairlady Z looked like but a lot of those parts are new and don't look "70's", even for Japan, I'd guess. The Subaru fart can exhaust tip, the newer wheels, the low profile tires, the racing seats (which he totally ignored when writing about the interior). Nice car, poor write-up. Did they use fender mirrors on 1975 280Z's? Sorry. Just back to my negative form... "Period Correct Z Perfection" is just too much though. It's not correct and it's certainly not perfect.

It's looking like everyone is so hopeful that there's some simple cause for your problem, that we haven't really considered the other parts of the engine. Won't rev, blows black smoke... why'd you buy it? Just kidding, but there are so many unknowns here that you should really go back to the very basics of engines. At least verify that each cylinder creates pressure (measure it if you can), check that the cam timing is correct (there's a notch and a groove), check/set your ignition timing (don't see that mentioned anywhere. Retarded timing will stop engine revving), at least eyeball the valves (set lash if you can), stuff like that. Go back to fundamentals before you get in to the details of the EFI system. The most common AFM problem is running lean in the mid-range. The engine will stumble and buck, you get mad and punch the gas, and it takes off because full throttle adds 27% extra fuel. Or the vane gets stuck and chokes air flow. But if the vane moves freely and you get 180 and 100 ohms on those two measurement, they usually work fine if nobody has messed with the vane spring setting. Just saying, you're starting in the middle of left field.

I looked at my 240Z prop shafts and that divot that Nissan took off of the yoke ears in interesting. I'll bet they used it to expose the cups so that they could clamp them down while staking. If you want some insurance for the clips, you could use one of the billion grades of gap-filling Loctite. Designed to lock bearing races down, which is what the cup is. Spendy but might be worth peace of mind. It could lock the clips on too, so they don't rotate and pop off. They have too many to know which might be best. http://na.henkel-adhesives.com/industrial/green-threadlockers-pre-assembled-wicking-13227.htm

These two seem to be still on the list. When people wash their engines they often describe a wet TVS/TPS as acting like a violent rev-limiter. The engine just stops at higher RPM. The water shorts it. On the ignition system, with reference to EFI and electronic ignition, the ECU uses just simple voltage pulses on Pin 1 to count engine revolutions and determine when to squirt fuel. If it sees too many it will squirt too many times. When the electronic ignition systems go bad they often spark too many times. When mine went bad the tachometer would read about 1.5 times actual engine speed. That's why I asked about the tachometer reading earlier. Just seeing spark doesn't mean it's working correctly. You might dig in to ignition. The GM HEI module is cheap, easy to connect, and good to have around as a spare anyway. The old factory modules are getting old and fail on a regular basis. And the pickup coils in the distributor are known to fail, with wires cracking and shorting as the breaker plate moves. Plus, pickup coil voltage increases with RPM and gets very high. High voltage shorts easier than low voltage. Still wondering about your part numbers. And if your AFM has been adjusted. The glue blob.

Just funny stuff from the eBay ad.

Rebuilt. @URGELIS

No need to apologize. I'm just pointing out that many people do what you're doing and it almost never gets them where they want to be. Just trying to help you down the path...

I see a lot of "correct"s and "good"s and questions that should be clear if you were in the right place of the FSM or Guide for testing. The only numbers you've shown are a couple of RPM values. The AFM resistance values are in the FSM. Easy to measure, even from the ECU connector. The way the FSM is set up is that if the continuity/no continuity super-quick tests don't find a problem then you go to the more time-consuming tests of actually getting resistance numbers. This thread is starting just like about 20 others over the last few years. No offense, everybody tries to find the quick "bad part" solution. Post as many numbers as you can measure, and include the AFM and ECU part numbers. Two kind of hidden ways to run really rich are a hole in the FPR diaphragm or a bad ECU. A bad ignition module can also send too many pulses to the ECU while failing. Usually that will also show up on the tachometer with funky needle movement. And, to make things possibly worse, if it ran bad when you got it then the PO probably messed with things to try to fix it. A common mistake is to adjust the AFM vane position. You might have to go through and reset almost everything.

So, capacitor, broken wire, or bad crystal (Xtl) are the things to consider. Curious - do you save your videos in a high-res format? My ISP is supposed to be 4O Mbps but I get the spinning circle on some youtube videos, like yours. I think it's just crappy CenturyLink servers but who knows. It's funny how bad the internet still is even though the "speeds" are supposedly orders of magnitude faster than 54 KB. Which was the fastest phone modem speed for quite a while. Just checking. Low res might get them to play better.

What's an Xtl? I have a 78 clock in my 76 and the old non-working 76 on the shelf in the garage. I'll have to watch your videos.

I fixed the power supply on my computer by replacing a capacitor. They tend to leak brown goo at the top when they go bad, if I recall right. Used it as a reason to buy a nice Hakko FX-888 soldering iron. On sale at Fryes. Enough power to desolder and a digital temperature setting. Much better than the old wood burner I learned on.

What brand of gasket? Might be more important. Did you have the exhaust manifold resurfaced? They tend to corrode if they were leaking before. A good gasket and smooth, flat, clean surfaces will save you a lot of redo time.

Here's a web site that tracks collector values. They don't have any 1981 data for some reason but 1982 would be close. Notice the condition page too. An auction that is well-followed by Z and ZX people is BringATrailer.com Known as BAT. Link below. Might give you some ideas. https://www.hagerty.com/apps/valuationtools/1982-Datsun-280ZX?id=124375 https://www.hagerty.com/valuationtools/Classifications-and-Conditions https://bringatrailer.com/search/280zx/

Nissan has the diff removal process shown in the Rear Axle chapter. Kind of weird. Many of us have tried to remove specific parts like you're doing, but the way they show is actually the easiest and quickest. Drop the whole assembly as a unit. The mustache bar provides handlebars for stability. Once it's down you can remove the mustache bar to get the diff cover off. You're not going to get those studs out so that you can slide the cover down. You don't need to drop it to the ground either. You can lower it just enough to get the mustache bar off. For future reference.

Probably won't really know until you get the parts. Might end up as garage art. Or, maybe, the clips will center the joint well enough that you feel comfortable restaking from the outside. If the fit is an interference fit you might even run with no stakes and no clips. One of those things that you "know" is fine, calculations wise, but still makes you nervous. You already know that the original stakes weren't really that strong.

Whoever these guys are they seem to be collecting a lot of Z car parts. Not sure about their pricing model, but if you need something obscure they might have it. A few examples. https://maseraticompound.com/products/datsun-240z-oem-engine-cam-timing-chain https://maseraticompound.com/products/datsun-240z-seies-one-e-30-rebuilt-engine-block https://maseraticompound.com/products/datsun-240z-oem-engine-water-pump https://maseraticompound.com/products/datsun-240z-oem-engine-water-jacket https://maseraticompound.com/products/datsun-oem-280zx-complete-engine