Zed Head

Your front brakes have been "upgraded". I think that Toyota calipers are the common one. Look around for "big brake" kits to see more. Welcome to old Z car world.

Actually, the wide open part isn't adjustable. So it might just be dirty or the wires are shorted. It's a fairly crude mechanism.

Not trying to overload you. That one test result, showing wide open throttle, should be causing your engine to run really gassy though. So you must have another problem, or that result is wrong. Easy to get the probes in the wrong spot. Once you have an out-of-spec. result though, then you can focus on what that part of the system controls.

Like site said, it's adjustable. Engine Fuel chapter. Really can't emphasize enough how one of the main things that make these cars so easy to own, fix, and maintain, is the availability of the free Factory Service Manuals. The TPS can get dirty also. Note that we call it the TPS but it should really be TVS.

You might have overlapping wrongness then. Because the test results would be showing the ECU that you have the throttle wide open. That adds 27% extra fuel to whatever the base calculation is, which should cause it to run better when cold and bad when warm. Gassy smelling and rough running when warm. But the fact that it runs better warm would indicate a lean mixture. Which could be a shorted coolant temperature sensor circuit (page 56 in the 1975 EFI Guide), indicating a very warm engine to the ECU, and removing fuel. That might be the popping when cold, but runs okay when warm. The ECU thinks it's very hot and removes fuel, but the WOT (3-18 continuity) indication adds fuel. Or you might just have low fuel pressure (lean), or clogged injectors, being compensated for by the WOT 3-18 results. 23 degrees is way advanced timing for the EFI engines. Spec. is probably 7 or 10. Many people run a little extra, like 12-15 to add some throttle response and a bit more power. You have an engine that runs which is more than many. But you have to get all of those small details right. Once you start knocking some down it's not a bad process. Set your timing to 7 degrees when warm for starters. That's where it should be. Picture from the Engine Tuneup chapter.

You can't get to the nuts that hold the studs unless you remove the inside panel. You need a think pokey thing to remove the rivets. And you'll probably lose some of the black spaghetti pieces.

You can't get to the nuts that hold the studs unless you remove the inside panel. You need a think pokey thing to remove the rivets. And you'll probably lose some of the black spaghetti pieces.

You're right. I even forgot that I gave somebody the same advice just a short while ago, that there was no guarantee the PO had it right. Even referred to it in my post above, "people get it wrong all the time". They get the oil pump installed wrong too. In that previous thread, the PO did have it wrong and the new owner put the wires where they were supposed to be. When he put them where they weren't supposed to be it worked like it used to.

Considering that the car had some questionable work done to it and probably sat for a while, have you changed the fuel in the tank? If it sat for over a year, it could have bad fuel. Also, fuel pressure is critical to proper operation of these systems. The tanks are known to generate rust and cause fuel pressure problems. Worthwhile to measure it. Good that you've already solved some problems and know more about the state of the engine. Might be worthwhile to tell as much as you can about how long you think that car sat, what, in detail, you've done to it since you got it, and how, exactly, it's running and driving.

Actually partial should have been many many ohms, like kohms (kilo-ohms, thousands) or infinite, and full should have been low, as shown. For Test 1 (2). But you're only saying open, not fully open. So not clear if you had the throttle wide open or only partially open. Either way, that measurement would show full throttle to the ECU, adding extra fuel. When there's continuity (very low ohms) on 3-18, the ECU adds a lot of extra fuel. Not clear what "running badly" means either. Is this driving, or idling, or revving? At least you know the timing is correct, Although you didn't report the number,or if it advances like it should when revving. Sorry, we've asked you step in to a messy world. But you know some things for sure now. I copied the test I think that you mean by Test 2. The TPS has three states - idle, not idle (partial), and full throttle.

Cars drag a pocket of dirty air behind them. The air passing over the sides of the car creates a pressure differential inside the car. The air pocket at the back is higher pressure than inside the car. So whatever is in that pocket of air will be pushed inside, through any small holes The hatch framework has holes that can't be sealed easily like where the latch attaches. The big vinyl covered panel on the inside of the hatch lid is open to the framework. It can be be sealed to stop the air flow. Simple adhesive weatherstrip will do the job.

Dave gave a good list. It looks long but each item is simple. Things get overlooked like the fact that the crankcase (the valve cover) is connected to the intake system, through the PCV system. So even a missing dipstick is a vacuum leak. And the tests at the EFI plug are simple "poke and read the meter" tests. Just resistance measurements. Grab a pen and paper and write down what you measure also. People often come back and say the numbers checked out, but don't say what they were.

You've reached thrashing about stage. Once you get here it's best to go back to square one and build back up. That would be to confirm that the plug wires are in the correct holes. Since you didn't remove the oil pump, it's probably safe to assume that the distributor is installed correctly. Take the cap off, turn the engine until the rotor is pointing forward and the timing mark is at zero. Then put #1 in and install the others in the right and order and rotation direction. People get it wrong all the time.

Correct ignition timing and firing order is critical.

Use this book to verify that the coolant temperature sensor is correct and connected, and the AFM. Your symptoms sound a little bit like the AFM isn't connected, and the engine is running on the idle enrichment only. http://www.classiczcars.com/files/file/31-efi-book-1975/

Everybody's just recommending that you check that the carbs aren't gunked up. Even a dry carb will get some slight corrosion of the aluminum that can cause friction, if it's in a moist environment. They're sensitive creatures. Sometimes it's worse when they're off because they might sit tilted. Then the varnish sticks on unusual parts.

I think that IGN is actually the fusible link that supplies those fuses. Just realized something. IGN, ACC, HL, and the main link (BAT). Not sure what ST is doing there though.

Site had it in two posts, first page. Damn. Not sure why the fuel gauge fuse would power the VR though. Maybe the wire wiggling helped out. This is from the 1976 FSM.

Looks like two problems, the seal area and the fit of the propeller shaft yoke. I think that steel outer shield is a press fit. You might be able to get it off by twisting and pulling. Nissan got rid of it in later years anyway since the propeller shaft yoke has its own shield. Once that's off you can work on the aluminum if needed. Once it's close though I'd take Euro's suggestion and just seal up the outer edge of a rubber seal and drive it in. You'll break the edge off if you do too much to it. Not an uncommon problem.

How long is "a while"? And where did it sit? Did you remove anything besides exhaust when you replaced the exhaust? These kinds of problems are usually caused by the stuff that you're sure can't be the reason.

There is no "they" it's just one guy named Al. And he will spin you a story. His member name on this site is URGELUS or something like that. He's saying that the ZX starter is stronger and lighter than the Z starter. Which it is. But you can buy the same starter for less money elsewhere. Al sells inexpensive stuff for a high premium. The real question is how he stays in business. The answer is people who fall for his stuff.

It's a shame that Wheeler Dealers bought in to his hype and have added life to what he does. https://www.californiadatsun.com/california-datsun-parts-blog/wheeler-dealers-240z-restoration.html?highlight=WyJzdGFydGVyIl0=

Here's the two starters you're looking at. $75 for a polish. https://www.californiadatsun.com/starters/datsun-z-240z-280zx-510-heavy-duty-reduction-starter.html?highlight=WyJzdGFydGVyIl0= https://www.californiadatsun.com/starters/datsun-z-240z-280zx-510-polished-hd-reduction-starter.html?highlight=WyJzdGFydGVyIl0=

Like site says, other companies use the Nissan gear reduction starter as a high-performance unit, by installing a different nose on it to fit other engines. That's just a shined up and painted gear reduction starter from CD. Probably from Rockauto. Browse his other products and you'll see that most of them are just inexpensive parts with slight modifications, and a huge price increase. Distributors with a mounting block added - 3 times Rockauto cost. https://www.californiadatsun.com/distributors-and-parts/datsun-240z-280z-e12-80-rebuilt-electronic-distributor.html?highlight=WyJkaXN0cmlidXRvciJd The factory gear reduction starters work well.

Should also note that people get bad alternators straight from the shelf. That's why they have a lifetime warranty. But if you're not getting power at the T plug, the alternator can't work. That's probably where your mechanic is stuck. Since the engine runs on the battery, focus on that.