kutukutu1

Yes, i am sorry. i meant "start". I will try the oil pressure sender trick to see if the pump stays on. Steve, I will check voltage at the pump after i go from "Start" to "On". Ill be post back later tonight with an update. thanks

The car will run for about 10 to 15 seconds after you stop cranking. It idles good and sounds healthy, then you see the fuel pressure begin to drop and it dies soon after. I have not tried starter fluid, but since the car starts every time since when i put the key to "ON" it turns on the fuel pump and builds fuel pressure again, it will start. i have not checked the coil to ground when it dies, i will do that today after work. Why am i checking this for? I really dont think its spark since it idles great for the 15 seconds that it does run. I should try to apply voltage directly to the fuel pump to make sure it stays on and crank it and see if it runs like that. If it does, then that would indicate that i am not getting any power to the pump after i let go on the key. correct?

Hello All, I have posted a couple of questions on other issues and i just want to say i will respond to those as soon as they are fixed, but one issue piles on top of another and cant fix one without the other. So, the issue i am having is the following. I start the car and it turns on, 10 seconds in, it dies. This is what i have done as checks 1) unplugged starter solenoid, fuel pump turns on when i put the key to "on" 2) Fuel pressure when cranking is 36 psi, but when i stop cranking, you can see the needle oscillate alot from the injectors firing and i am thinking the fuel pump is not staying on after cranking. then you see the pressure start going down until it dies. 3) Fuel pump relay checks out 4) Fuel pump control relay check out as well, everything works on it 5) AFM fuel pump pins 36 and 39 have continuity when i move the flap, but when you look at the 78 schematic, that circuit in the AFM it says useless and its not used, but everywhere on the forum on similar topic, they say to check the AFM fuel pump control circuit. If i try the typical check of moving the flap to see if the fuel pump turns on, it does not since that circuit is not even in the stock wiring. 6) I have tested the pump straight and it works and builds pressure 7) When i checked the pump the pressure was a steady 36psi which tells me the pressure regulator is good What should be my next step? Thanks

Thats an awesome list. Thanks

It is not the thermostat switch, to see if it was the switch, i unplugged the connection to the switch and just jumped the connection with a wire. When i do that, the same thing happens and it drops to 7V. The AC relay is not unplugged, you think that could be a possible culprit? Ill unplug it and test that out as soon as i get my injectors back on and the engine started again. Ill post back as soon as i try it. thanks

I tapped into the relay line for the AC. I dont have an AC system and the connector had been damaged so i used that line since it was a switched 12V. thanks

If i read that point to ground, i get 12V.

Sorry about that. I wired it per the diagram it came with. https://derale.com/product-footer/product-instructions-footer?download=251:16739&start=240

Hey all, i made the install and the fan works fine, but i have the most bizarre issue which i cant figure out. The install kit comes with a wire so you can put a manual switch to turn on the fan on top of the thermostat switch turning on the fan. So the fan turns on with the manual switch, but here is the strange part. If i dont manually switch it on and let the thermostat switch do its thing, reach temperature, it does not turn on the fan unless i give it a jump start with the manual switch. If the temp switch is at its working temp, i have to toggle the manual switch to get the fan going, then it stays on. I used a voltmeter and checked voltage going into the temp switch, i get 12V, if i jump the switch with a wire, suddenly the voltage drops to 7V. When i jump the temp switch there is nothing in the circuit but wires and the fan so i am at a loss as to why thats happening and why when i give it a jump start with the manual switch, it does work. Any ideas?

Nice work. Keep it up.

Clean looking car. Love it.

It is not stock and i have never had it off. I just recently acquired the car and still go thru a plethora of issues. Ill take it off and see whats going on in there. Thanks.

Thanks all, yes i finally found in the FSM and its the horn relay. I currently have no horn connected so i just hear the click. I should just pull the steering wheel and check the ground?

All, 78 280z, EFI. There is a relay that is under the glove box, right next to the vent pull knob. I dont know what is for, but it clicks when i turn the steering wheel. It only clicks when the steering wheel is at a certain position. If i go full lock either way it does not do it. Does anyone know what that relay might be and why it would click when i turn the steering wheel? Thanks,

Thank you all for the response. Ill get these ASAP.

Does anyone know if they sell pigtail connectors for all the efi system? My AFM, TTS, Coolant temp, FIDLE all have connectors that are broken in some way. they still work, but can fall off. I looked around, but could not find any new.

If the rules allow it, i say change it and put the GM one. If you keep the original, you need to connect the T connector. The GM 1 wire is easy to connect, 1 battery cable, terminal #1 gets ignition 12V and Terminal #2 gets the voltage sensing wire. If not follow the schematic since its an external voltage regulator. Again, if the rules allow, use an internally regulated alternator.

Ok, So S goes to #2 and L to #1. Ill find S in the harness. From the schematic it looked like the L went into the S. thanks.

Injector cooling fan? Ill look at the Taurus and see what they got. Some controllers do have a tuneable controller, but i really hate to have that box somewhere under the dash or in the engine bay. It looks out of place. If the switch works, i am good with simple.

Ok, SO i finally pulled my alternator and its the SI 2 terminal alternator. Here is my understanding. The WR goes to the terminal lug, i understand that one Terminal #1, i know thats switches 12V, but from the original harness, which wire should i tap into? the WR from the original voltage sensing in the schematic seems to be connected to the same wire that gets connected to battery on the original alternator, which would tell me thats not a switches 12V. Terminal 2, i know which one is that wire, but i dont understand the connection in series and the resistor in parallel. Which other line are we talking about? i only have the L wire, which on the original schematic also connects to the voltage sensing. thanks

Alright, so i took out the sensor and to my amazement, the previous owner just got the original plug, drilled a hole in it and put one of the aftermarket radiator temp probes and rtv'd it to seal it. I might do the same thing, since it was not leaking, but anyone try this switch? Does anyone know if it fits in that unused hole? Looks like it might. https://zcardepot.com/electrical/switches-and-relays/electric-cooling-fan-switch.html

If its a switch, it would be ideal.

Thanks for the help. Ill take it out tonight and see.

I agree, i have not found the plug either, which is why i was searching and found zero information. I would like to use that 4th threaded hole in the Tstat to use for my efan, anyone know the threads? The sensor that it currently has is no good.

I dont have a picture right now, i can post one later. I know for sure its not a stock efan. Its mounted in front of AFCO aluminum radiator as a push fan with some brackets that are clearly not stock. I just havent seen info online on this circuit. Capture 2 shows where the wires come from in the fuse box. The WR only comes from the fuse box. The L comes from the fuse box, goes to that efan sub harness from the first picture, also splits to go into the combination gauges and kickdown switch for automatics. I am not as concerned with using this circuit, i can always do my own efan wiring, but i thought, why not if its already there. My biggest question is if anyone has seen a sensor on the T stat housing like i have? What thread is that port? If you know anything about it, where can i get a replacement sensor? Ill post a pic of the sensor later today.