so i swaped an s4 13bt into my car. for some reason the fuel pump on my car wouldnt iniatate when i turned the key, well being the lazy *** i am i just found the pin on the ecu where the fuel pump connected and just hard wiried it straight to the fuel pump. well i finally got the car running but for some reason it keeps cutting out at 4 to 5 grand, like theres a fuel cut or soemthing. a wieser person than my self told me it was the secondaries but after thinking about it for a little, i remembered someone saying that the voltage changes to your fuel pump when you get on it. i was wondering if because i hard wiried it in, it would cause there not to be enough fuel running for the secondaries to kick in?

 

How 'bout that. I had no idea you could hardwire the fuel pump to the ECU. Learn something everyday.

Do you have a fuel cut defender? Know what one is? Do a search and you'll come up with some amazing information about them.

Secondarys coming online are a function of Boost sensor seeing a value and the rpms hitting over 3800 rpms. Actually if you disconenct the vacuum line off the boost sensor and cap the LINE , then rev the engine slowly to the 3800 plus range and over, the secondarys will come online and make the engine sound *funny* until you rev much higher than thirty eight hundred.

If you did not install the fuel pump resistor relay assy off the turbo car onto your n/a, then there will be no change in voltage to the pump. It'll be batt/alt voltage all the time.

Fuel pump connected to the ECU. I gotta look into that. Where's the FSM and the pictures.

https://www.rx7club.com/forum/showthread.php?t=116095