Hello, I have 04 G35 coupe AT, I read online that I should do as many breathing mods as possible before putting resonated test pipes on my G and so I installed a stage-2 Takeda cold air intake, along with a Z1 plenum spacer and a muffler delete. I noticed that once I start it up I gotta give it one or two revs otherwise it sounds like it wants to give up or its not receiving enough fuel. Everything else is stock and its not tuned yet.
Anyone knows what fuel mods I can do or how to fix my starting problem?
Also I plan running my G without a tune until next year thats why I tried to add as many breathing mods as possible

 

First thing I would do is reset the ECU. The ECU basically self learns its own fuel trims over time, and when you start making changes (intake/exhaust) it can throw off the ecu. It will probably adjust over time, but not nearly as quickly as with a ecu reset.
When I replaced my knock sensor and sub-harness, I installed a MD 5/16" spacer. My car ran like crap after immediate install. Idle was rough & bogged/hesitated. I reset the ecu with Datascan2 ('clear self learn' function), and oh boy did it wake up the car. Throttle response was much more crisp and I'm getting ~1 to 2 mpg better mileage; I attribute most of it to the knock harness being bad.

 

Hey Andrew do you know if by disconnecting my battery for a couple of minute it would also reset my ECU? I dont have the software but i’ve seen videos of people disconnecting their battery or doing some sort of sequence from inside of the car to reset the ECU. I am just not sure it works or if its even safe to do it in any of these two ways without having issues later on.

 

Just disconnecting the battery takes a while to reset the ECU (24hrs?). Disconnect it and bump the brakes to discharge everything and reset ECU quickly.