NewZed

The brake check warning lamp relay is powered off of a yellow wire from the external regulator in the stock configuration. If you or someone did some rewiring at the old regulator harness that could be the source. Easy to check, the relay will click and there will be a small spark at the negative post when the battery cable is re-connected. Take the cable off and put it back on a few times, listen and look. The relay is under the passenger seat. The brake pressure differential switch lights the lamp but shouldn't cause a draw if disconnected.

You read my mind. BRAAP wrote up a good summary of his L6 experience, see Post #4 specific to TB's and the whole thread for general knowledge. http://forums.hybridz.org/topic/95316-braaps-l6-efi-induction-advice-and-tips/

Is the ECU getting the right temperature signals? Engine runs good when cold with rich air/fuel mixture, terrible when hot and super-rich. Check at the ECCS plug.

Turbo engine?

From the Google - http://www.ngksparkplugs.com/tech_support/spark_plugs/faqs/faqcode.asp?mode=nml

They're not very complicated, just some throttle-actuated contact points. Have you taken the cover off to see what's happening, and how do you know it failed?

You can also do the math in Delta's spec sheet. Those are all measured numbers. Theirs comes out to 1.5 (.466/.3104). Subtract the lash out and you get 1.47. I'm just doing math on numbers available, not real rocker arms. Delta actually measured the lift on ww240z's cam, so the math is kind of moot for his wonderings. Looks like they added lash back in to get "gross". The bulk of the internet and literature uses 1.5, so the fight to change thinking to 1.4 will be a good one.

If you look at pages EM-29 and EM-30 in the 1976 Engine Mechanical chapter you can derive 1.5 and/or 1.6 ratios yourself. If you calculate in the hot lash numbers you'll get ~1.53 (intake and exhaust different), if you ignore lift lost to lash you'll get 1.57. Both above 1.5, no way to round down to 1.4. Later FSM's, ZX's for example, don't have enough numbers to do the math.

Is your real question about the price of the head rebuild or whether you really need one or not? The cost of the rebuild would depend on quality and quantity of new parts, how much time is spent, and the mechanic's valuation of that time. Value of the job is what it's worth to you.

The other points of pressure leak down are the check valve in the fuel pump and the FPR. Are you using the stock FPR or aftermarket? Aeromotive FPRs are known to leak down rapidly.

If you have the stock ZXT transmission I don't think that it has a reverse synchro. Might still be air in the lines. Looks like fun.

Probably something under the hood. Open it and see what you can find. Use a multimeter.

You said it runs great in #15...? Popping and stumbling is typical of a bad AFM causing lean spots or just running on the lean side due to low fuel pressure. I have two lean AFMs that work fine with the potentiometer in the water temperature circuit, adding a little fuel.

Try here - http://www.datsunstore.com/240z-260z-280z-c-203.html?osCsid=37b8da3c7da41f308568397ec5001165 Looks like some are out of stock, but it would be worth an e-mail or phone call to be sure.

The solder joint fatigued and broke underneath the big blob of solder. Looked like it was still connected but was just sitting above, no electrical connection. If you were pressing down on the shiny solder blob with a probe you might measure continuity or voltage, that would then go away when the probe was removed and the wire end lifted. I think that it's fairly common. It's a heating/cooling/vibration fatigue that cracks it. Grab the wire and tug. If it comes free, that's a problem. C-1 is where the actual ground point is. Maybe you lost ground there. Find C-1 and jumper the pin through the back side or something, or measure voltage at the pin with the switch on. The diagram of C-1's location and the rheostat pin is on the page I referenced above.

Weird how the brain automatically converts unknown words in to known ones or some sort of mutant word that sounds more familiar. E-prong from EPROM. Someone that has Nistune might be able to read the chip and learn something. If modification dates are saved. Assuming that Nistune was used. It's possible that the ECU was "chipped" but even then it would be difficult to tell unless the new or old chips have ID numbers. You should re-title your thread "How do I tell if my 88 Z31 ECU has been chipped or Nistuned?" Where'd you find this "tuner"? Craigslist?

Coincidence? Did you have your hand on something else while fiddling with the dome light? The dome light has constant power but only grounds through the door switches or the switch at the light itself. BE-16. My instrument lights and running lights went out when the wire to the top of the switch broke off. But ti sounds like you've checked that, and confirmed it's good with the hedlight circuit swap. How about the rheostat circuit? That's the ground for the instrument lights, through C-1 which, coincident to the lights coming back on, is down by the fuse box. BE-15.

Tuning would most likely be done using Nistune. Rewriting the internal EPROM. No hardware changes, so the inside will look the same. http://www.nistune.com/equipment-products.php

76 does not have a pump prime. The 76 pump only gets power at Start and when the AFM contact switch is made to the fuel pump relay. Your memory of a fuel pump prime may have been a dream about a ZX.

Don't the bump stops bounce off of the top of gland nuts under full compression? Could be a clue re your suspension bouncing off the line when racing. Probably related, get off the bump stops and the gland nuts might stay tight.

You figured out FSM. BE = Body Electrical. The ZX FSM does not have a Body Electrical chapter, but does have an Electrical chapter. That would be the next logical place to look. Have you tried to figure out what the one (1) switch does? Is the 5 speed from a ZX or a Z? That would be a factor in number of switches.

Free, or salvage value? Title? Parts only or possible restore to driveability? I haven't been to Eastern Washington for a while.

It's an acronym. The middle letter stands for Service. You could also take a multimeter and measure what's happening on the wires under various conditions. Reverse, neutral, key on, key off, etc. Puzzle it out. Or you could just drive the car around and see what doesn't work anymore.

Word.

Exactly. You're getting worked up at someone who's on your side.