Ok, after doing a lot of rebuilds (AAV, WUR, FD, Plugs, Plug Wires, a lot of tubing) all was working perfectly I had a very nice high idle of 1200rpm then when warm back to 1000 steady, no hunting, no issues, the car runned flawesly until.... the car just started and then off and will not start again, i checked the FD and pushing the MIX I confimed there was not pressure on the FD... so removed the saftey switch and no fuel pump. Removed the fuel pump 15A fuse.. and it was dead but with its legs ok (no overheating, it just worked and died on load, and not in a bad contact overheating). I replaced the fuel pump fuse with another 20A trying to get back home, but when started the fuel pump Relay started click very ugly, not only seen, but I could also touch it and feel its heavy vibration... I stopped the engine again and switched it with the external ligths realy... the car started but had a very ugly running, and fuel pump is making a higher/different noise and ended in general bad performance, but could get home!! So my plan is 1) get some new relays (the ones there are the original ones), and go back to a 15A fuse. 2) install the new fuel pump ( I already have it) and fuel pressure regulator (and maybe change fuel filter again?) 3) remove and clean the internal tank screen (fuel filter) But any idea of other source of this issue? What was the relay clicking? it could be a false contact in the safety switch for example??
Looking at the diagram, the fuse box has 3 relays on the right hand side , top is “i”. Fuel injection start relay, centre is “t” relay for fuel pump, bottom is “v” relay for ignition switch. From what i can see they appear to be inter linked. Not sure why it has 2 fuel pump relays ?
The relay chattering is probably the primary side 12 volt signal cutting in and out. A relay has a 12 volt supply to it and the relay is energized by the primary circuit, you seem to have an intermittent signal to the relay.
Chances are if you have the original metal relays, the fuse board is original as well. Most (including me) change to new relays when doing the board swap. I can't tell you the number of electrical gremlins I continually chased until I finally bit the bullet and bought the newly constructed fuse box. (GT Car Parts).
ok good, i think there is a chain of issues here, where even the fuse box is not the source... I can feel, but not sure, there are a lot of chained issues that create a lot of work at the fuse box and make them fail. as said in the beginning, I will do the fuel pump change, since i'm sure its the original one and pressure regulator, and fuel filter (again, just incase) and fuel tank filter... but before doing the fuse box (give me time!) i will do another try with a delayed-off realy for the fuel pump, just in 2 seconds value. the idea is any noise, bad signal, bad trigger, or faulty security switch sensor, will not make the realy (and the pump, and the fuse) to go crazy... it will close at anything above 1V for 2 seconds... so that will avoid fuseboard overheating and more... It could be very, very interesting if there is a low trigger relay to... because for what I see, normal trigger (high v? >10v) on high consuming componets like the fuel pump is a key to disaster....
exactly, there where several sympthoms detecte... i'm not sure what was FIRST... if the ticking blown the fuse, or the fuse (change later) started the ticking after... the car was OK, and in the next min, 3 symphtoms (relay click, fuse box blown, fuel pump strange noise) appeared at the same time (even a 4th with the fuse box being really hot) but can not be 100% sure which was first if it helps, it was a 35C temp day, very warm... so everyting was working hot.
You can plug one of these into the fuse holder to see how many amps it is taking Image Unavailable, Please Login
It might help to know which relay exactly was chattering. The fuel pump (far right middle), or the fuel pump starter (far right top) ?
Just an update: the Pump made a very bad noise, the tank strainer/screen was rusted+clogged and a lot of bad stuff going there: i'm doing a full refresh of the lines, strainer/screen, tank cleanup, fuel pressure regulator, fuel filter, etc, etc, etc... all will be new. Image Unavailable, Please Login
as addendum, the source of the issue was the fuel pump dying, the new fuel pump worked with the old relay without issues (just for testing, I replaced it anyway) looks extreme consumption + heat can make the relay to bounce some how
