I have the E6K, walbro 255lph, completely rewired 10ga directly to battery on ground and relayed and fused through ECU harness on positive side. all connections are soldered... heatshrunk where applicable. even the relay connectors were depinned and soldered by me so I know every connection is good.

I had the car running for about a total of 25-30 minutes. fuel pressure was about 43 the entire time. From the beginning the fuel pump would prime and then shuf off. but it would turn back on when the engine started up. so once it was running it would keep the pump on.

The issue im having now is that it curently will prime the fuel system when the key it first turned on for a couple seconds but the the fuel pump will not stay running. The only way i can get it to stay on and running is if I run a jumper wire to the switched ground signal side of the relay directly to ground. This is the ground signal that the ECU (E6K) provides to turn on the fuel pump. Any Ideas why it might be doing this?

 

That's how it's supposed to work. Don't understand the question.

 

This is how it initially worked... Now it does not turn back on once the car is running... If the relay is not grounded manually the car will not run..
I grounded it to the batt... It runs.. If I disconnect it the car dies. The ecu isn't sending the ground signal to the relay except for priming... Unless I'm missing something...
Thanks Chris!

 

No idea. E6Xs were known to have an issue with the fuel pump circuit, but they just wouldn't come on at all. Never heard of anything like this.

 

HAHA Oh great.....

 

If i cannot resolve this would it be ok to just ground the relay permanently so the fuel pump runs continually if the key is on? or put it on a switch?

 

yes, you can just wire the pump to your own switch if you need to. Having the haltech control the pump is more of a safe guard, so it doesnt allow the pump to continue running if the engine is stopped for any reason (ie. car crash)

 

Do you know of any reason why it wouldn't leave the pump on? Any safety or anything?

 

its a safety. if you flip the car or get into an accident, the engine will probably stop running. in that case, if at zero rpms, your pump wont be priming constantly and helping to feed a fire. by default its on. you can turn it off if you so wish.

 

So could this have anything to do with why I have no tacho? Also if it doesn't start right away would it kill fuel? If I jump the relay and start it the laptop reads tacho...

 

Maybe.

It has fuel pressure in the line. thats what priming does.

If the tach functions with fiddling with the fuel pump relay, then something is up.

 

With the relay jumped to ground on the switch terminal the engine runs and tach does not work. Must not be related..

Man I am at a loss and feel like an idiot.....

 

Anyone have any ideas?

 

so with the fuel pump relay jumped, the car will start and stay running?

 

Correct... And if I disconnect the negative jumper to relay while its running it dies...

 

honestly, the simplest solution is to do as you have done, and build your own relay/power supply for the fuel pump. Luckily, in my situation, I already have my fuel pump wired independantly for my full S4 swap, so i have something to fall back on if my E6K decides to be non-cooperative

 

I don't like that tho because something obviously isn't right...

 

post a wiring diagram of what you have going on.

 

and you've tried a new relay?

 

have not tried a new relay... ill have to make a diagram

 

The tach output and the fuel pump output are most likely not related. The tach output probably needs a pull-up resistor to 12V. I was using Halwin to try to talk you through the setup but finally got the old laptop out and actually looked at the DOS software and there is no pull-up option in it. My guess is, if you add a 1K ohm resistor between the aux out wire and 12V, the tach will work. You still don't get to program it in the software, so it may not be accurate.

For the fuel pump, you could probably use one of the outputs setup as an RPM switch. Turn it on at 100 rpm and off at 12k. This way, if the engine stops, so will the fuel pump.

 

Ok so connect 12 key on power to aux out/ tach circuit with 1k resistor?

And I'll try that with rpm window switch output.

Thanks!

 

https://www.rx7club.com/haltech-foru...ensors-993942/

This picture shows a pull-up resistor installed on an input. Basically, you'll do the bottom half of the picture with the output and 12V instead of 5V.

 

Does wattage matter? RadioShack has 1k 1 watt and 1k .5 watt... Ill solder it in like your picture... I know you said you like the cased ones but will this work for now? It will be inside the vehicle... Also can I heat shrink a resistor?

 

Wattage is basically how much heat the resistor can reject. I have no idea what the amp draw is on the circuit. I use 10 watt resistors for pull-ups for the gauge senders and they don't even get warm. I would guess the amp draw to be very minimal. Use the highest rated of the two you have available and monitor it to see how warm it gets. I wouldn't cover it in shrink until you know just how warm it gets.