For those who have upgrade injectors and a UTEC, how did you tune out the hot start issue? My start up is fine cold, but if I try to start the car after its warm it initially revs then stalls out. if i blip the throttle on startup it will hold idle fine as well.

 

i dont have any hot start issues. whats your fuel pressure?

 

I had the same problem using 650cc RC injectors. I fixed it mostly using Osiris, but not completely.

 

fuel psi sits between 40-42psi. str8dum1 if you dont mind me asking what values are you using in your 0% load column for 250, 500, and 750 rpm? Maybe its dumping too much fuel on startup.

 

anything above 440cc injectors with the utec will cause this.

 

and theres no way to tune it out via the utec? I guess I will have to grab a reflash.

 

I just tap the throttle when the car is warm on restart and no problem, if it wants to stall out, I turn on the A/C and it bumps up the revs enough to let it run fine.

 

the issue is that the utec doesnt take over until the car is running, not during cranking.

i guess some cars are just more sensitive, bc mine only had a hot start issue like 2 times in the past couple years.

 

This is exactly what i have to do on EVERY warm start. Its kind of annoying since now its habitual and I even do it when I'm in the wifes car.

 

I just changed out my battery on my stock '03 350z...now I am having this same problem..starts fine when cold..but on a warm start after the initial surge the engine dies...if I give the throttle a nudge it idles fine....any thoughts?? Anything I can reset myself??

 

I got the same situation after the battery is dead, then stalling issue. I sent my ecu to Injected Performance to bump up my idle. The car is running fine now. No more stalling. Also people who have bigger injectors(hot start) with Utec, try to get your ecu flash to scale for the bigger injectors. Everything thing can be done via ECU re-flash with IP for $400.

 

If it was fine before the do the idle-relearn procudere.