I posted this on Driver and got nothing so I was hoping you guys might be able to help me out.

To make a long story short, I have an 07 G35 6mt coupe. I had to replace the engine and ecu. I had the ecu programmed to the key but the car still won't start. I tested everything and the fuel pump is not receiving power.

I left the shop and while I'm taking a weekend break from it, I was just thinking how the Maf sensor is disconnected and the Accelerator Pedal sensor is disconnected and was wondering if any of the two would keep the ecu from powering the pump.

I know it's a long shot but iff anyone can help me on that or any other way to troubleshoot it, I'd appreciate it.

 

The pump should start on ACC so i dont think the MAF or pedal sensor would stop it from going.

Check the fuse?
The same ECU came with its original motor? Try your old ECU or another one?

Any codes?
ECU has power right?

 

Yeah, I just read the service manual and the pump is suppose to operate for 1 sec on ACC but mine doesn't. As I was reading how to diagnose it, it said to check voltage between the ecu pin and the condensor pin. What is the condensor part it's referring to?

I might have to try another ecu. Just hate paying 100 a pop to program the key to them. Don't have the original that came with the car.

The only codes are for the maf and pedal sensors and p0183 Fuel Temp circuit A high output. No bcm codes so I know the key is programmed to the ecu.

 

fuel pump fuse is good right? and all other fuses for that matter?

Sucks with the whole key programming thing, makes things difficult, got to take care of one thing at a time but to verify one thing works you have to have the other one work....

Might be worth it to pay for a partial installation before doing a few $100 programs

 

I checked all fuses and the pump is good. The only thing I can think of is if the next computer I use doesn't fix it, to wire the pump so it runs when the ignition is turned on. I'm not sure if that's a good idea or not though.

 

Your new motor is out of a 2007 also?

Wonder if there is a harness issue somewhere

Pump relay?
ecu ground?

Im just spitting out ideas

I did a rb25det swap and had a similar problem and actually did wire it straight to battery, i think it ended up just being the pump relay, a fuse or a ground.... keep going over it and you might win, but it could be a different situation

 

the key is programmed to the bcm