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A few of you may know this. But last year I designed and made a coil on plug bracket based of Bryan Blake’s ford coil on plug design. It uses the Nissan coil head used on the Nissan GTR R35. Works perfectly, bolts on and you can even buy a very nice pre made wiring harness from platinum racing products. Coils are fairly cost effective. Takes a specific boot (2-3 actually work) to work. It’s one of the best coils on the market. I believe only the AEM coil beats it. Basically he took my design based off of his, then fixed some of my issues and is now selling them. Bottom pictures are my bracket installed on my 240z. Email Bryan to place and order. Eventually he will sell on eBay. bryan@blakemachine.com

Hi All, I'm brand new to this club/forum, but have found a lot of value in it over the last few months. My dad, son and I started a project car a few months ago. It is a car we bought from a kid who took it apart and couldn't figure out how to put it back together. I think we're 99% of the way getting it back together and running, but we're struggling with an EFI issue. This is a very long post, but hopefully that helps rule out some of the initial suggestions guys have and drill into the real issue quick. Just to answer the standard questions: We have fuel to the rail and can hear the fuel pump running. We have verified spark. We have tested pin 1 on the ECU connector and verified there is a pulse coming from the coil. While turning over, there is no motion of the tach. (Not sure if that is normal prior to engine start or an indicator of an issue.) When we spray a little carb cleaner into the air intake, the car tries to run for a second and then dies. When I tested the injector connectors with a standard test light connected to ground there is no signal/light. I tried with a Noid light as well and no signal/light while in run position on ignition or while turning over. We did the checks for "Engine will not start" on page 22 of the FSM EF section. The only one that didn't pass continuity was 1-(5), Water Temp Sensor. The others were all at .000 except for AFM which showed the following results: 6-8 = .182 7-8 = .194 8-9 = .102 I'm ordering a new Water Temp Sensor, but I have a hard time believing that would keep the injectors from getting a signal. I have already replaced the EFI Main Control Relay with a NOS I found. The original one burned out the Fuse Link wire instantly when we connected power. When I connected the new one (Part number 2523079903 in exchange for the original 2523089970, All of the exchange part numbers I could find said that was the correct one.) What I'm stumped on is when we did the checks on page 25 "Continuity check using Voltmeter" Check 2-(1) and 2-(2) were fine but every check under 2-(3) failed. So zero results on cylinder 1-6. Any suggestions on what might be causing this? A few forum threads have mentioned the wiring to the alternator could be an issue or possible the oil pressure sensor or wiring could be an issue. It sounds like the Fuel Pump Control relay relies on these. I'd like to check both of those, but I'm struggling finding the proper test procedure for those in the FSM. (and to be honest, am not sure I need to because the fuel pump is running, but I'll try anything at this point.) Any suggestions where I can find those tests in the FSM? I'm going to replace the oil pressure sensor just to make sure. I took the alternator in and it is charging, but maybe it isn’t communicating with things correctly even though it is charging? I didn't check the fuel pump relay or fuel pump control relay because I can hear it running and we have pressure to the rail. That's next on my list tomorrow though because I can't tell from the wiring diagram on page 24 if where pin 73 on the EFI relay goes to the fuel pump control relay pins 95 & 97 could be keeping the EFI relay from sending a signal to the Drop Resistor and main harness to send power and signal to cylinders 1-6. A couple other things we've done: We did an ohm check on the drop resistors as directed in page 34 and it came back fine. We did a ohm check on the line between pins 43/1 &43/2 on the Drop Resistor and pin 43 <73 edit> on the EFI main relay and it came back fine. But when we checked for voltage on the drop resistor side of that line there was no signal. Not sure if that is normal though with the Drop Resistor disconnected. <Edit, As I was looking at the diagram, I may not have put the correct number in the sentence above. I thought I tested the 43 pin on the plug for continuity to 43/1 &43/2 on the Drop Resistor, but I believe I actually tested 73. Sometimes it's hard to tell which pin in the FSM I'm testing. If you look at the plug, with the green wire on top middle, I tested continuity from the bottom right plug to 43/1 &43/2 on the Drop Resistor. I need to verify this tomorrow because I don't see how continuity could happen the way I'm remembering testing the plugs in my mind.> Not sure it matters, but figured I’d notify just in case. This car is a ’78, but the dash came out of a ’76. The kid had damaged the dash so bad I used a mostly assembled dash from the ‘76. Someone on another forum thread mentioned the tach could be causing an issue for another guy’s EFI problems, but he was getting power to his injector connectors, so I’m less convinced that is an issue for me. Thanks for any help

Hello everyone, and thanks in advance for any help you can give me. My 1976 280z was running fine last time I drove it, but after sitting in the CA sun for 2 years, I'm struggling to get it back on the road. After draining out the old gas, I have a new battery, new spark plugs, and a couple gallons of new gas in. When I go to start it, all I get is cranking, and no turn over, and I have yet to hear the fuel pump cone on. I've tried moving the new battery to the rear and getting 12v to the fuel pump directly, but this doesn't get the fuel pump going either, just a click. I also don't seem to be getting power to the fuel pump when cranking. Any ideas on what might be going on, or existing threads on this that I can go off of would be greatly appreciated. Thank you, Oscar **Also zero fuel pressure when cranking** *Reading taken under the hood, after the fuel filter*

I have 2 of the stock 75-78 280Z throttle position switches. One is new. I bought it to use on my L28 and ended up having the car totaled by a talentless Firebird driver on I680 a few years back. The other is used. MSA lists these at @$90 but NLA. So let's use that as the price for the new one. The used one at $25. Both are plus shipping and should fit in a small Priority Mail box

My 1976 280z won't rev past 3500 when not in gear, and about 2000 when in gear. When in neutral it will blow clouds of black smoke at higher rpm. It has run way to rich like this since I bought it. I have checked the wiring and sensors and rectified the issues I found to no avail. The water temp sensor was the first place I looked, I replaced it when I first got the car. It is giving the correct reading all the way to the ECU and has a noticeable effect when I unplug it. My only guess would be a AFM, I have two but don't know the condition of either. They both passed the ohm tests, could there still be an issue with them? If not what else could be causing such a rich condition, especially at higher rpm.

Z ran when parked Had it running in January after I chased down a misfire issue that came from a faulty ECU. She ran mint so I began my tear down, months later here we are and I thought Id have it running today but no luck. Heres what I got so far from trouble shooting. My battery is fully charged (tender says 100%), its less than a year old. My digital multimeter has it showing about 12.8 yet when I put the car on the "ON" position, my battery gauge in the dash reads about 8.5. I tested the ECU pins with a dmm and it will read 8 and change. Is this normal? Is this a fault in the voltage regulator? I tested the 6 pin connection that goes into the voltage regulator but didnt have much daylight to really spend time on it. About 3 of the connections read battery voltage, I think 2 read around 4.2 and 1 read really low, I forget the number. Fuel pump works when power is applied directly from an outside source (getting proper fuel pressure at my regular and fuel rail gauge when applied) but not from the car itself. The FPR reads 0 and you dont hear any fuel going to the rail. No leaks. Through testing the fuel relay from the ECU pins, I wasnt getting any reading so Im certain the relay is faulty. I bought that today and am just waiting for it. Could this potentially bad relay be causing all these gremlins? Spark is coming from the coil but no spark at the plugs. Something is up with the dist? I checked the AFM through the pins of the ECU harness and that looks perfect. Another small thing I noticed, when I hit my horn button, my tachometer will jump!! What is going on with my Z? Thanks!

Hi all, Some time ago a fellow member Lenny was in the process of making an aftermarket ECU which would be a bolt-in replacement for the standard ECU. It was a great idea and I was hoping it would be a success. Unfortunately Lenny was sided tracked and the project stalled. I like the retro EFI in the 280Z, but I would like to have something tunable and it’s getting harder to find good functioning parts for the 280Z. Now for so something I never thought I would do: Fit an aftermarket ECU. Now how to go about it. Which system should I use and should it be a complete swap or partial swap????? The choice soon came down to 3 systems. 1: The LinkECU G4+ Atom or the G4+ Storm. http://dealers.linkecu.com/atom 2: Spitronics Mercury 2. South African system for 2 up to 12 cylinders with lamba sensor. http://spitronicsuk.co.uk/category/install-guides 3: Perfect power XMS5B. German system for 4, 6 & 8 cylinders systems with lamba sensor. https://www.perfectpower.com/index.php/products/stand-alone/xms5a Megasquirt was not in my short list because I couldn’t find anyone locally with tuning experience. In the end I chose the Mercury 2 because a friend is using it in a Toyota and getting great results. The technical people at Spitronics are friendly and didn’t hesitate sending HEX files of different systems that would work on the L28. They had some files for a 280ZX and a L28 with EFI. You can also download a lot of stuff from their website. There are so many possibilities on the mercury(like the others) from single coil to coil on plug with wasted spark and injection pulsing twice per revolution to sequential injection. I would like to start simple with my single coil and running my Bosch low impedance injector in pairs on 3 drivers. I’m am now busy making the harness and brackets for mounting the ECU where the old unit was. To do list: 1. Assemble harness 2. Make bracket to mount ECU 3. Make adapter to fit Bosch TPS variable resistance sensor 4. Make bracket and fit MAP sensor 5. Remove AFM 6. Machine plug for Lamba and weld in exhaust pipe. 7. Remove all unused equipment. 8. Tune it enough to run and eventually dino tune. Need to drive it 45km to the dino shop with Spitronics experience. I don't have much time atm, but the car is now in for the winter, so that will give me some breathing space until March next year. I know it's a long first post. I'll post some photo's of what I have done soon Chas

Hello I just bought a 1976 280z, My first z but i have done a lot of research on them. It will start up easily and run cold well at around 800rpm. But once it warms up (the temp gauge is about in the middle.) It will drop down to 500rpm and stutter. If I give it barley any throttle to bring it to 800 rpm it is fine but if I go up to 1000-1200rpm it will back fire through the intake and exhaust. The plugs are back but not fouled. If I manually control the AFM it will run fine. I also unplugged the connector to the cold start injector but it did not seem to change anything. I am thinking the temperature sensor is the problem. also there might be some vacuum issues because of any dry rot (I plan to re-do all of the vacuum lines). I do not a lot about how the efi works on these cars except for the basics, and I would like to know how everything works. -Thank you

Hi I have a 78 280Z that wont run. 2 Owner California car, very clean. I had it running when i bought it, but it always started rough, backfiring and sputtering. After replacing some hoses, I drove it about a mile and it started running very rough and had a major loss of power. I have checked for spark and fuel pressure (you can hear the pump running, too). It will crank and not even backfire or fire at all. Compression is also good. I do question the wiring because the pins on the ECU/ computer and the leads on the fuel injectors do not correspond with a wiring diagram I have. Faulty crank sensor? I have replaced all the easy ignition stuff- Wires plugs cap rotor. Really at a loss, ive never worked on anything with EFI and no OBDII before. Thanks

Hey Everybody, A few months ago I acquired myself a rust bucket 76' 280z (mainly for parts and drivetrain) I want to get the engine running to confirm that it is worthy of holding onto. Somehow I cannot get the injectors to pulse. The car fires right up when hit with ether and will run as long as ether is supplied. BEFORE everyone goes ahead and says it I DO have the EFI BIBLE and have gone through it best of my ability to follow the testing suggestions. What I've done so far: Pulled all 6 injectors, tested that they open and produce fuel, not clogged. Have a NEW Fuel pump hooked right up to the fuel line. Connected back at the tank so that the pump activates when cranking. Checked all four fusible links on passenger side of car with volt meter. All seem good. Ran a Negative jumper from coil to pin 1 in the ecu. To eliminate bad ground wiring in harness. Checked pin 10, 20 for fuel pump circuit and relay. Injectors have a current, they are lacking their ground from the ecu when I crank. Did a pulse test ( ran a negative to the - terminal of coil, with key On grounded it on the body quickly to check for pulse) got all six injectors to pulse a few times. They only pulsed a couple times and then this didnt work anymore.) From here I'm not sure what else to do. I read that maybe I should check out the dropping resistors? How would I test these? Also how would I test the EFI Relay? Thanks in advance

Recently bought a Z and am sorting out the issues. It runs albeit on the 3 rear cyclinders. New fuel pump, new NGK wires and plugs, distributor looks like it was replaced not long ago. Coil looks original (new MSD blaster in the mail). I know it's getting fuel, spark and air. I know all 6 injectors are functional. Just not all at the same time. When I crank it, it starts almost instantly, when I place my screw driver to each injector, only the rear bank makes the clicking. Removing any of the front 3 injector pig tails doesn't affect idle. When i place the rear 3 injector connections on the front 3, once again it starts and idles the same. Is this a fault in the first bank wiring harness? A dropping resistor issue, faulty ECU? Currently I only have the FSM available on my phone and I'm diving through it but I feel overwhelmed. I checked the pins with a multimeter and each injector is getting current. Did I miss something simple? Thank you for reading. Hope to hear from you guys soon. PS, I bought all new injector connections, but that doesn't seem to be the issue despite them being worn. Haven't installed yet.

Hi all, while rummaging through my storage unit I found a complete EFI system for a 1978 280z. I remembered I pulled this system out of a working 2+2 car before I parted it out. For some reason, I kept the system in a few boxes in my garage. Anyway, the system is complete with an intake manifold, fuel rail, injectors, computer, harness, and filter box. Let me know if you're interested and how much you're willing to pay. If there's enough interest I'll have to go back to the storage unit and take some photos. Thanks! Mike

Engine turns over, then stalls. Checked all fusible links, no issue. Fails first test of the EFI bible...no power at the plug to ECU.. Could use some advice, please.

Hi all: I searched here for the answer, and I Googled a bit for a source. But no luck so far, other than Ebay, which has connectors that don't look the same as mine. I noticed on my '77 (that I just bought) that the AFM connector does not seem to have any retaining means in the AFM. If I unbolt the AFM, the connector falls out as soon as I move it. I'm concerned the connector will fall out while driving. Is there a source for a replacement connector, aside from getting an entire harness? I can't even tell what is supposed to retain it. But I assume this is not an uncommon issue. Before I shell out $300+ for a harness, I'll explore a home-made solution. But I'd rather replace the plug (or whatever retains it if that can be retrofitted). Thanks in advance, John.

My apologies if this is a duplicate, the system seems to have just swallowed my carefully crafted posting (telling me I wasn't logged in). Here goes again. I just bought a 1976 280Z as a project car. The body is in good shape but its been partially dismantled. The previous owner took it apart to move some performance parts to his new Z. So it came with the EFI intake/throttle off the car (along with a bag of misc stuff). Exhaust is missing (I have MOTORSPORT TBC Coated 6-1 Header, and MSA premium exhause on order from the Z store). Bumpers are off. Interior taken apart. Drum brakes need work (in-progress - Front disks/calipers look great though). Previous owner upgraded distributor to ZX/electronic, replaced fusible links with fuse block, new dash cap/carpet. My first goal is to get it put back together and running to see what I have. Since the EFI intake/throttle is off the car I decided to replace the injectors (on order) and clamps (one side of the fuel rail had standard hose clamps rather than EFI clamps - looks like one of the injectors was replaced a while back). I have mostly stripped the manifold and would like to give it a good cleaning (along with the throttle which I have removed). What is the best way to clean them inside and out? Carb cleaner and elbow grease? Have it dipped? Something else? Putting it all back together will be an adventure. The previous owner did mark the wiring harness (I will clean all the contacts with deoxit) and I found the Datsun EFI Theory/Troubleshooting book on-line - I think most of my questions will be answered there. I will replace all of the vac hoses and any water/fuel host that doesn't look new (some look newly replaced). I have a new throttle gasket on hand. I will get all new injector hold-down bolts (not screws!) and tighten them appropriately when I reassemble. Any other suggestions while EFI intake is off the car? What would you do? Thanks, Dan PS, Here it is:

Hi I'm new to this page and the car only owning it for 2 months. Being 17 and being used to dealing with carburetors. So to the issue it is running rich I have replaced the coolant temp sensor and the 7th injector plug, have adjusted the air/fuel screw also but still getting too much fuel, please help.

This is probably a DUMB question but.... I'm replacing all my gauges with Speedhut gauges to include their oil pressure and coolant temp units. I see from the FSM that both of the stock sending units go to the EFI control unit. Also, the new units require the use of their sending units. So... 1. Will the elimination of the stock sending units for oil and temp cause a problem with the fuel EFI control? 2. If I use Speedhut's sending units, which must be of different current and/r resistance than stock, be OK? 3. Do I need to keep the stock senders in place and ADD the new ones just for the gauges? If yes, does anyone have any recommendations on the best way to do so? Sorry for the multiple questions. I found many related threads but none touched on this issue. Thanks!!