SteveJ

I have a bunch of photos of cars doing that in Turn 10B at Road Atlanta.

Let's be specific and precise. Is there still a plate in the driver's side door frame? Can you read the date? What I post assumes that this fits into what is considered the 1978 model year. If I understand you correctly, when you put the key in the START position, the solenoid engages the starter. The starter turns the engine, and the engine fires. (The car starts.) When you release the key to allow the switch to go from START on ON, the car dies immediately or shortly after. (It doesn't run.) I'm not sure what you mean by running the fuel pump right out of the fuel rail. I will have to assume that you have an adequate supply of good gasoline to supply the fuel pump. Here are two possible causes for your problem (though there can be others): The back part of the ignition switch is failing. The circuit for the fuel pump relay is losing the ground at the oil pressure switch. How to diagnose (You will need a multimeter, i.e.: a meter that can measure voltage and resistance.): Ignition Switch Put the meter on DC voltage. If it has ranges, select the lowest range that is above 12 volts (probably 20). Put the positive lead of the meter on the positive terminal of the coil (black wire with white stripe). Put the negative lead on an unpainted surface. I like the bolts of the shock tower. Have someone start the car. You should see around 10 to 12 volts while starting. When the key is released to go from START to ON, make sure you still have voltage. If the voltage drops to 0 when the key is in the ON position, that means the switch is bad. Oil Pressure Switch Put meter on the lowest resistance range. The oil pressure sender has a "T" connector. The oil pressure switch connects to the vertical of the "T". Get one probe in the back of the wire to test. The other probe goes to an unpainted surface. Again, I like the shock tower bolts. Have someone start the car. As the car starts, you should see the resistance measurement go to zero (continuity). If the resistance does not drop, that means you don't have the probe positioned properly, or the oil pressure switch is bad. Let us know the results of these tests. Also, post pictures of you holding the leads in place and of the meter. Please don't post potato quality pictures. Sometimes people don't use the proper technique, and that provides bad results. I don't want you throwing parts at the problem. That gets expensive and frustrating.

To go with @Racer X's comments, hardware kits: https://www.thezstore.com/page/TZS/CTGY/classic19o And header gaskets: https://www.thezstore.com/page/TZS/CTGY/classic19a

Since you kept talking about it, @Captain Obvious, I decided to take the plunge. 😉 While @Dave WM is trying to see if it's just the meter, the description of the behavior during the trip tells me it is the charging system itself acting up. By the way, Dave, I like the current monitoring setup. The ammeter I linked would work the same way. As long as the place you clamp the meter feeds the white wire in the wiring harness, you should be good. You may want to get a voltmeter that plugs into your cigarette lighter, too. The lights getting brighter tells me your voltage is going up during the issue. I'm betting you'll see the voltage go up when the ammeter says you have current flowing to the battery. The ammeter behavior seen in your video looked typical to me. You have the voltage drop from starting the car, so the alternator is replacing the battery's loss. You didn't have to crank long, so it doesn't take long for the battery to get back to a sufficient level, dropping the alternator output. Let's consider the operation of the VR as laid out in the wiring diagram. As the neutral of the alternator builds sufficient voltage, it energizes its coil in the VR. The contact that closes provides a ground for the second coil that is powered by the battery. Note that this second coil is wired in series with a resistor, probably to drop off the voltage and cause the coil to de-energize should battery voltage drop from discharging. When coil 2 is de-energized, the switched voltage is going straight to the field wire on the alternator (full field voltage). When coil 2 is energized, the switched voltage goes to two resistors (voltage divider) to reduce the voltage going to the alternator field, dropping the alternator output. From reviewing http://www.secondchancegarage.com/public/83.cfm it's obvious for the mechanical VR the contacts would constantly open and close. With a solid state VR, you have discrete components handling the same function in a similar manner. Here's the thing. If the VR is not dropping the voltage going to the field wire, you're going to see increased output from the alternator. Keep in mind that a flaky ground at the VR could present itself in a similar fashion. I am assuming you're running a solid-state VR. Also, a flaky neutral could also cause the problem. It could also be a winding issue in the alternator if the grounded leg has a winding shorting out close to the neutral. (I don't think you would have an intermittent short on a winding, though. I don't have enough practical experience to say one way or the other.) Ideally, it would be great to monitor the voltage on the white/black wire with an oscilloscope. You would expect it to fluctuate too much for a typical voltmeter. Monitoring the voltage to ground on the neutral might reveal good data, too. Okay, now I need to find all of my O-scope probes so I can see if I can configure something for an educational video.

I like how that fits into a standard relay base.

It looks like it might have had floor repairs, but what caught my eye was "unrestored" in the description of the car. You can clearly see overspray and paint flaking around the door jamb tag. Given what we have seen from "Beverly Hills" lately, I hope people look for another car.

Time to get a slide hammer and possibly an air hammer. On the passenger side of my 260Z, I was working the slide hammer while my friend was getting the other side with an air hammer. It finally cooperated. Oh, and I suggest not using the 280Z for a long distance drive again until after it has been addressed.

Interestingly enough, I am an admin for the GZC group on Facebook. Someone joined the group to try to sell his 77 2+2. He asked for suggestions on where else he could list it because he was tired of the unhelpful feedback he was receiving from members of other groups. I told him to post the car here since I was pretty sure that adult behavior would rule. He listed the car here last night.

Ah, since you seem to have eliminated the VR from potential causes, I would think it's the stator or something related to the stator.

I would suspect that the voltage regulator was messing up if you were seeing voltage spikes. The symptoms you described would be along the lines of a loss of sensing (maybe from the VR overheating) causes current injection into the stator of the alternator, kicking up the voltage. However, shortly after that, sensing resumes, the system stops injecting current into the stator, dropping the voltage of the alternator (maybe too much). Is your charging system stock, or do you have an internally regulated alternator? Edit: I forgot to add that you could get something like this to get a voltmeter in your car: https://www.amazon.com/gp/product/B07VZFSY4SInsert other media

I saw it once before, 13 years ago. A gentleman was selling a 260Z on Craigslist. He dropped the price from $3,200 to $2,500 because it wouldn't run. It took me a while to figure out what was wrong as I was much lower on the curve for diagnostics skills, but I finally pulled the coil wire off the cap and saw pretty much what @chaseincatsfound. The seller got his $2,500, and I got the 260Z.

To add to what @Zed Headsaid, start with page EE-19 in the factory service manual. As the FSM says, make sure you have a fully charged battery before you test. Test the alternator and regulator. Added: Oh, I forgot to mention, make sure you have the proper tension on the alternator belt.

I'm pretty sure they would still be needed.

From the instructions on Holley's website: I used the configuration in Figure 2 for the 12-804 FPR, but again, I did not use a stock 260Z or 240Z fuel rail.

@Dave WM I came across this in a recent search on Amazon. It could serve as a way to confirm whether there's an issue with the shunt or charging system. https://www.amazon.com/dp/B01DDQM6Z4 You could mount it on the battery cable and run the cord inside the cabin. It's not for precision measurement, but it would definitely pick up if the battery is discharging from a bad charging system.

The main difference between the 260Z and 240Z fuel rails is the vapor line IIRC. There is a return on the 240Z fuel rail. I would install a fuel pressure gauge before the fuel rail without the FPR and check that. I found many pumps produce less fuel pressure than they advertise. Of course, I also didn't measure the voltage at the pumps to see if that could have caused the lack of pressure.

You have not provided enough information to give you an accurate answer. Why are you considering installing the Holley FPR? What fuel pump are you running? Will you be installing a fuel pressure gauge to set the FPR properly? Are you still using the stock fuel rail? It regulates the pressure with a fixed orifice. When I used a Holley fuel pump and FPR, I deleted the stock fuel rail and ran braided line to the carburetors. The order of the system was tank to filter to fuel pump to FPR. From the FPR one line went to the carburetors, and one line went to the return line back to the tank. I fabricated a custom heat shield to block the heat from the headers and ran the fuel lines closer to the carburetors as opposed to the stock fuel rail running near the valve cover. This made it where I didn't need to worry about heat soak.

I have three HF floor jacks. Two are full-sized aluminum, and one is a small steel model. They all have performed well for many, many years. I have jackstands that are over 20 years old (pre-recall) and look & work totally fine. Not all of their tools are one-use, but I wouldn't consider many heavy duty. HF actually has come out with higher line tools, too. I bought a couple of Daytona brand jacking dollies for a friend, and he bought two more. They work great for moving cars around in his garage. HF offers some tool chests that are similar to the quality that you find at the big box home improvement stores.

The blower motor part number is the same for AC and non-AC cars: 27161-N3600

You can test with a noid light. https://www.amazon.com/gp/product/B07QCD5CK8

You are correct, @Zed Head. The Mazda pump is for carburetors. I think the first fuel injected RX-7 was the GSL-SE trim. That was not offered for the 81 RX-7. @280zdude, I am running a Walbro 395, but I have a GM TBI system in my car. So far, I've run it over a year with no problems.

You will need a probe that can reach inside the connector at the fuel pump relay. That will also mean you will need someone to move the flap in the AFM while you are measuring voltage. You will not see voltage for the fuel pump relay unless the key is in START or unless the key is in ON with the AFM flap open.

Describe the testing conditions: Key position? AFM flap? If the key is on ON with the flap closed, the relay is not going to complete the circuit to supply power to the fuel pump.

Don't look at the fuse. Pull and test for continuity or just replace. Fuses are cheap.

Again, it's most likely the fuse. One of the idiosyncrasies of the headlight wiring is that there is one positive to each headlight and two negatives. This is why a bad fuse shows up as a dim headlight. Here is a breakout of the circuit with arrows to show current flow with a positive to negative convention. Treat the filaments as resistors for modeling what it wrong, not as coils. Most of the current going through the right headlight is going through the high beam filament, to the red/black wire, to the high/low beam switch, and on to ground. However, the saying "Current follows the path of least resistance" isn't really correct. Actually MOST of the current will follow the path of least resistance. Some of the current can find an alternate path to ground. It goes through the low beam filament, over to the low beam filament of the left headlight via the white/red wire, through the high beam filament of the left headlight, and out to the red/black wire. The high beam of the right headlight sees enough current that the brightness appears normal. Meanwhile, the left headlight has about an amp flowing through it. If you were to measure the voltage drop across the filaments you would see something like this (with a 12VDC source): Right High Beam: 12VDC Right Low Beam 4.55 VDC Left Low Beam 4.55 VDC Left High Beam 2.90 VDC Light output falls off drastically with voltage (https://www.thetruthaboutcars.com/2019/06/piston-slap-droppin-knowledge-on-headlight-wiring-voltage-drop/), so that is why the left headlight is dim with the loss of the left headlight fuse. If you don't believe me, do this test. Find a 240Z/260Z/280Z that has stock headlight wiring (no relay conversions). Pull one of the two headlight fuses. Turn on the headlights. @Randalla I suggest you try my suggestion first. It is EASY to change a fuse. Change the left headlight fuse.