After reading a bunch of threads on here, which were helpful in eliminating some of my other questions, ive got a question. I have read the the 78's FI were different than the other years. Where is the FI relay and dropping resistors located at on a 78'? I have the entire dash off and i can trace the ecm harness all the way into the engine bay and they do not ever split off to a relay or anything. I looked right above the ecm where the FI bible says they are and also a 77' FSM (used to own a 77') said they were, but nothing. My problem is my injectors are not firing. I have fuel to the rail, and spark but the engine wont run. If i spray starting fluid in the intake it runs fine until i stop spraying. Went to test the FI relay plug on the ecm connector and there isnt one. The PO says that this car drove perfect before it sat for a year.

The description from Hayne's:

Dropping resistors - Extract the two screws which secure the resistors to the fascia panel.

Relay - Same description as above.

Maybe the illustrations will help.

Yeah that helps. None of my local parts stores had a haynes for a 78'. I ordered a FSM for a78' last night so hopefully that will keep me from getting on and wasting anymore of your time. Thanks again.

The Haynes I have actually covers 1970 thru 1978 and can be confusing as far as year/use goes sometimes, but touches on most subjects and has great illustrations. A Thread that will be worth watching as it develops in time is here:

http://www.classiczcars.com/forums/showthread.php?threadid=28927

Where is the FI relay and dropping resistors located at on a 78'?

The EFI relay is the top one in the relay box under the hood on a 78. The dropping resistor is located behind the wiindshield washer bottle.

Yeah that helps. None of my local parts stores had a haynes for a 78'. I ordered a FSM for a78' last night so hopefully that will keep me from getting on and wasting anymore of your time. Thanks again.

You don't need to feel like you're wasting our time. That's a legit question and you seem to have researched it an not found an answer. At least, not a correct one. I searched for that relay when I bought my car ten years ago. Everyone said it was under the dash. Not on a 78. The dropping resistor is behind the washer bottle, under the driver's side inspection lid and I think that's true on all years of the 280Z but the EFI main relay in in the relay box under the hood, behind the passenger side strut tower on a 78.

I pulled the entire relay box out. It has 5 relays in it, 1 of which was not used. The fuel injection relay does not click or make any noise when you turn the car to the "on" position. Is there another way to test them out of the car, like running a 12v to one of the pins and grounding another and getting some voltage out of another. Actually none of them clicked or made noise when the car was on. What are the other plugs for? I beleive what i read was that the ecm runs through the relay and then to the injector harness, correct? So if the relay was bad, could this could explain both my fuel pump problems, and why the injectors would not be pulsing?

The very bootom was not used. The big one above that had a lot of blue wires, the one to the far right i believe is the one ofr the fule injection relay and i dont know what the others go to.

There are two relays to operate the fuel injection systen, two to operate the fuel pump, and one is for the air conditioning.The dirty one in the picture is for the a/c.

Pg BE-6 of the FSM.

BTW, there isn't a Haynes book specifically for the 1978 280z. It's for the entire S30 class, with a supplement for the 280Z.

The signal goes through other sources before it gets to the relays. A bad ignition switch or ignition relay could prevent the signal from getting to the relays. I've tagged the relays in your picture. You really need that 78 FSM. Don't shoot current through those relays until you read the test procedures in the EF section because you could damage them. I doubt that they're bad anyway and your problem probably lies elsewhere.

EDIT: TomoHawk is a faster typist than me but I thought you'd understand it better if I used your picture.

No problem, Stephan, I just grabbed a picture out of the FSM.

Yeah i know i need the FSM and usually i would wait to get it before i asked a bunch of questions but man i want to drive my car. Thanks guys, that helps alot, now lets see if i can get this thing to run.

Thanks for this thread, y'all. Now I don't have to post saying "help me help me".

Don't feel bad...I've had my Z for almost six months and I just now figured out it was a '78. The fella I got it from said '77, the paperwork said '77...but none of the advice for a '77 made any sense. It made for a very interesting time troubleshooting.

Has anybody got a source for the EFI main relay? The coil on the one I've got is burned out. I jumpered the plug, so I know the car runs, but I'd really rather have a working relay there.