So my buddy has an SR and this is whats happening. His running JWT ECU.
When its cold and you start the motor dies, but when you disconnect the MAF, she start up and stays running. No Ecu fault except for the MAF because it's disconnected. But when the motor is warm, you connect the MAF. Motor runs ok... So his thinking his fule pump might be the problem. But If the fuel pump is the problem why does she stay running with the MAF disconnected?

Any thoughts on what it can be fellas?

72nismo wrote:So my buddy has an SR and this is whats happening. His running JWT ECU.
When its cold and you start the motor dies, but when you disconnect the MAF, she start up and stays running. No Ecu fault except for the MAF because it's disconnected. But when the motor is warm, you connect the MAF. Motor runs ok... So his thinking his fule pump might be the problem. But If the fuel pump is the problem why does she stay running with the MAF disconnected?

Any thoughts on what it can be fellas?

I don't think it's the fuel pump itself, but a voltage drop at the fuel pump is definitely possible. I've seen similar issues with bad batteries. Does he have a wideband? When it's running "ok" how lean is it getting?

If its the voltage drop on the fuel pump..why she starts and stay running if you disconnect the MAF?
And I tested the pump running directly to see if is the pump but did the same thing...

Z32 Maf

It seems like when the car warms up make the sensor to run ok which would be the cas, coil packs, .., and if that is the problem what's the connection between those sensor to the MAF?...

72nismo wrote:If its the voltage drop on the fuel pump..why she starts and stay running if you disconnect the MAF?

With a voltage drop at the pump, you lose pressure in your fuel rail. Your injectors are set to be opening with 43.5psi of fuel pressure. With the pressure drop, you end up starving your engine of fuel. Once the MAF is disconnected, it goes into "limp mode". In this case, it is set to run rich (injectors are open more), so you now get enough fuel to run properly.

72nismo wrote:Z32 Maf

What's the rest of your setup?

What is done for tuning?