Hi guys, i am having a cold start hesitation on my MR.
i just go the engine back from the builder, and have a based break in tune in it. the car drive and idle normal, AFR is where is should be. however the cold start hesitate is what makes me concern. it will take about (5-10sec) to crank up the engine. my tunner said it is normal for bigger injector and told me not to worry about it.
my engine mods are below.
built block
214b cam
1300cc ID
walbro 450
boomba rail
wtf inline fuel filter
gtx3576r
map 3.5 intake
map afpr kit
let me know what you guys think? is it possible the battery is dieing?

 

I would doubt its the battery but you can just get it tested for free and rule that out. But just wondering do you turn the key and give it a few seconds for the fuel pump to prime everything or do just turn the key all the way to starte really fast? Maybe give it a few extra seconds before starting it.

 

I had the same thing as you. Im also built with almost 1000 break in mile (getting tune in 2 weeks!) My tuner said to check my relays, the one for the throttle and the MFI, I bought the 5 relay kit from SSP put in on and had not had that trouble since.

 

my relay are new from SSP, so i doubt they had the probelm. i am thinking about might be the afpr kit is defective or fuel check valve is missing when my shop install the fuel pump. does anyone know where the fuel check valve is for the stock fuel system?

 

priming it doesn't work either. i remember when my car was stock, i had no issue with starting.