SteveJ

According to the owner's manual for 79, it does not need leaded gas.

Try and buy it. I'm betting there are some parts from it that I want, too.

Well, I found that I'm missing the driver to use the USB cable to log data. My computer didn't like the CD that the driver was on and fouled it up, so I ordered a new driver. The fuel pressure gauge should get here tomorrow. I replaced the fuel filter and took it for a spin. I am more convinced that it's a fuel delivery issue more than an ECU map issue. The car drove smoothly for a few miles and then started feeling down on power and bucking. I got it home and looked at the plugs. They looked great. I got in the car again and took it to the end of the street. I started in 1st and wound it up to 4,000 RPM. Then the RPMs started going down. I didn't cut the old filter open, but the gas coming out of it looked clean. I'm going to do another round of testing when I can collect more data, but I'm starting to lean more toward a surge tank.

Clip leads are easy to find: https://www.harborfreight.com/18-inch-low-voltage-multi-colored-test-leads-66717.html. Just drive over to Modesto. As for the ignition relay, let me check my supplies and PM you.

Okay, I looked in the FSM. I don't like how that test was written. (Mind you, I work on industrial control systems for paralleling generators, so I'm used to relay logic.) 90-91 does NOT have continuity. It will have some resistance as you're reading through the coil. If 93-92 had continuity when voltage was applied to 90-91, the relay is functioning as designed. 94-95 does NOT have continuity. It will have some resistance as you're reading through the coil. To elaborate on what I posted in the other thread, 94 is normally grounded at the alternator. 95 is positive from the ignition relay. 96 is grounded at the oil pressure switch. 91 goes to the fuel pump relay. 97 is positive only when the key is in the START position. The oil pressure switch is closed when there is no pressure. So in a "no oil pressure" situation, both coils in the relay are energized, and the fuel pump relay coil is energized if the car is starting. Once the car has started, the oil pressure switch opens up, and the fuel pump relay coil is energized from the ignition relay via the fuel pump control relay. It would not surprise me if the ignition relay is the culprit here.

I'm not sure if this works, but it comes up on Advance Auto's cross reference: https://shop.advanceautoparts.com/find/1978-nissan-280z-fuel-pump-relay.c7634 Z Car Source lists exchanges for the Fuel Pump Control and Fuel Pump relays. https://zcarsource.com/used-nissan-280z-fuel-pump-control-relay-for-the-1977-78-starting-in-august-of-1977-datsun-280z https://zcarsource.com/used-nissan-280z-fuel-pump-relay-for-the-1977-78-starting-in-august-of-1977-datsun-280z

I should add that the ignition relay is NLA. I have made replacements for people by utilizing conventional off-the-shelf relays.

You have me at a disadvantage here. I do not have a 78 280Z, and the wiring diagram does not have pin numbers from the relay. Could you post a photo that shows the pin numbers so I can verify your findings?

I'm not sure it is critical to have the baffled tank. The problem still happened with a full (and I mean FULL) tank. The baffled tank wasn't mentioned on the Patton Machine thread on HybridZ, and Rick Patton doesn't mention it on his website. Keep in mind that his primary customers are British car owners. This system also operates on a lower pressure and lower flow than the Bosch based system in the 280Z.

Actually, I was contemplating a less redneck way of doing things (though it would be untrue to my roots) and buying a sender and a gauge for in the cabin. At this point, $100 isn't that much more to spend.

Len, Considering I don't have much experience performing diagnostics on FI, your input is greatly appreciated. I hope to change out the fuel filter this weekend and test, weather permitting. First, I'll test in the garage to make sure I am data logging. The software wasn't designed for an operating system as advanced as Windows 7, so I might have to find a refurbished XP machine. Once I confirm I can log data, I will go for another drive, and I will try to note the time response. Like so many others on this board, I'm not a spring chicken, so I'm not going to rely on my memory about whether the power loss was fast or slow. However, I don't recall hearing any backfire, and that I'm more sure about. Considering the fact that my engine is not stock (2.8L with higher compression and possibly a non-stock cam), it could also be a combination of filter and map. It helps to keep in mind that with the SUs, I previously had issues with being a little lean toward the top end and used 1/3 racing gas to help prevent detonation. By the way, welcome back.

Look at this thread. I describe the operation of the fuel pump relays for the 78. https://www.classiczcars.com/forums/topic/62552-78-280z-turns-off-with-turn-signalreverse-lights The interesting thing about the linked thread is the time it took to resolve because the problem was upstream (corrosion at a factory splice) from where the OP and I thought the problem resided. Basically, here is what you need to do. Verify that you have good connections between your battery and all of the fusible links. Verify you have the proper functionality at the relays. Verify the proper functionality of the oil pressure switch. Verify the proper functionality of the ignition relay. The most important thing is that you need to be able to use a multimeter well. If you don't, find someone who does. You'll also need the wiring diagram. @wal280z has created a color version of the 78 diagram. He may be able to tell you where he posted it. It may also be available in the downloads section of this site. I have a link to the downloads section in my signature (visible if you are on a computer).

Are the hoses in good condition? Some small cracks will let in air and make it where the pump isn't able to move fuel.

Also, John Morton will be driving that BRE car at the 2019 Classic Daytona & Daytona Historics in November. I'm looking forward to seeing photos of the car on high banks.

Randy Jaffe's BRE isn't the original, but he has the original powertrain, two of the surviving wheels, switchgear, gauges, and many of the other bits and pieces from the original car. Dan Parkinson bought the 46 from BRE and raced it for a while until a front steering/suspension (I can't remember what exactly) failed and put the car into the wall on its left side. Dan got a 280Z from Nissan and transferred the parts to that car. Randy bought the Parkinson car a few year back to get the parts. Some of the parts just sit on display, like the powertrain. Other parts have succumbed to time, like the megaphones. (I was helping the team scrounge for parts when the megaphones gave out at the 2018 Mitty.) The car has been recaptured in incredible detail, down to having hand-painted numbers and logos. To see it in person is to travel in a time machine back to the 70s. John Morton even gave Randy the VIN plate from the original car.

Thanks for the input. It does have the ability to datalog. I haven't done that, yet. I still need to change the fuel filter. I can't remember if I changed it when I did the bumper swap. If I didn't, it's been on there a while. Then I can do the datalogging. After that, I can send the info off to Affordable Fuel Injection for a different map.

It wasn't having issues before the conversion. I drained the tank completely a couple of years ago for the bumper conversion, and I didn't notice much in the way of debris in the gas I drained out. Of course, when I look at the filter carefully post change, my opinion of the condition of the tank could change.

Well, I tested the car this morning. It doesn't like starting smoothly, but once it got going, it ran nicely...for a while. I was going up a hill, and it started losing power, like fuel starvation. I decided to add fuel, almost 7 gallons. It drove well on flat roads (little elevation change), but on a rise a few miles later, I felt the loss of power again. The road leveled out, and I made a right turn. Again, under load, it didn't have enough fuel. I'm going to change the fuel filter and increase the pressure a little on the fuel rail. I have also started researching surge tanks just in case.

I remember looking at snowmobile throttle cables a few years back. Those looked promising to me.

I have a set still in the box I could sell you for $999.49 (less than $1000) ?

On the northwest side of Lake Lanier Yes, on http://fiddlingwithzcars.wordpress.com and https://georgiazclub.wordpress.com/2016/06/12/making-new-memories-284-photos/ No, I don't sell them. I bought mine from Group Harrington.

If you want to see the stainless steel bumpers in person, I have them on both of my cars, and I'm within a decent driving distance.

Also https://whiteheadperformance.com/product/new-datsun-240z-260z-280z-stainless-steel-euro-bumpers/

https://groupharrington.com/product/datsun-240z-and-260z-bumpers/ Stainless steel bumpers

To be specific - Use a threaded plug with a good coating of anti-seize. Otherwise, it's likely that you are still welding up the O2 bung. I'm pretty sure I used anti-seize on the bung for my headers, and I still had a bear of a time removing the plug.