No fuel!!!

[skylinedriver59]

Ok so my Z was running great it had a minor bug I need to work on but overall it was perfect so far. However now I have no fuel. I’m running an L28ET with z31 ECU and MAF. Like I said car was running great but for some reason I have no fuel I checked everything and narrowed it down to no fuel pump relay signal from the ECU. My signal use to come out of pin 20 and it was a ground signal. The car still runs after I run direct power to my pump. But even then it won’t start I have to use starting fluid to get it going. I’m hoping I have a loose ground somewhere, but where? lol Just when I was happy now this. Has this happen to anyone before? Anyone have any advice or suggestions?

[evildky]

I'm guessing this car is a 71? meaning it had no electric fuel pump until you put one in? what pump did you use? what fuel line and return line did you use? ths stock return line is small and restrictive, and wellt he supply line is restrictive as well so lets hope you used the stock feed line as a return and ran a new suppy line, the car also had no wiring in place for a fuel pump so you ran a new hot wire and ground so you'd know if the ground were bad right? then it's a matter of power and I've ntp done the z31 ecu conversion, I've doen the l28et with stock wiring and with megasquirt, and in both cases the fuel pump is wired to a relay and the relay si triggered with a wire form the ecu, so do you have good power to your relay? relay good? getting trigger signal to the relay? any fo this help?

[skylinedriver59]

Yes you are correct its a 71. I installed a MSD fuel pump as well as a new feed line and used the old feed as return. I checked everything I possibly could MY relay is good and my relay also has good power coming in as well as a good connection to the pump. I have no trigger signal from the ecu. However I was checking grounds and when i was loosening one of the grounds the relay started flickering as well as the pump. So if i play with that ground the pump will flicker and turn on. i changed the connector as well as tried grounding it somewhere else but no luck.

[AZ-ZBum]

This generally means the ECU died on you. See if you can find another one in your area to test.

[skylinedriver59]

I think I burned two other ecu's, they started smoking. Most likely I have a short in my harness that keeps burning ecu's. I’m trying to save the money and get the courage to go megasquirt II. What do you guys think?

[AZ-ZBum]

Better fix the wiring before you fry another ECU or install any aftermarket unit.

Nistune seems to be the latest thing that people are going to.

[evildky]

are yoiu sure the ecu is recieving cranking power? it fuel pump and fuel injector relays recieving cranking power? this is a common wiring mistake

[skylinedriver59]

my injectors spray when I crank and I also have spark when I crank

[evildky]

the injectors fire when cranking, but is the fuel pump pumping while cranking? sometimes the optical distributors feil knocking out one or both signals intermitantly

fwiw, i love megasquirt, I've megasquirted both the L28ET and the VG30ET, but if your distributor goes wonky it won't help, also you did the z31 ecu conversion, has it run right since? did you replace the wheel inside the distributor?

[skylinedriver59]

injectors fire when cranking but fuel pump doesn't. And YES it was running great with the Z31 conversion I did the conversion a while back and this problem just came up. I also replaced the wheel inside the distributor.

[evildky]

so if nothing changed then it has to be a parts failure (although the fuel pump should have cranking power) have you checked the ecu for codes? thats the nice thing about the z31 obd ecu conversion, you can check codes

[skylinedriver59]

Its been a while since I've done a ecu scan for codes on a Z31. But If I recall I just have to move the test selector and check for the red and green lights for codes then return the selector to its original position after im done.

[evildky]

sounds about right