Nistune Forums

So i just recently installed some 550cc injectors and can not get the car running with changing the settings in Nistune.

*Car will run if injector settings are untouched which it's just dumping fuel at this point


I have tried reloading the base map and starting from scratch,
I have adjusted latency settings to spec, changed the injectors from 270cc to 550cc and it just cranks
Pretty much not sure what else i can do at this point

My injectors are:

Nikki
Connection:Denso/Sumitomo
Resistance: 13.5
Dead time: 0.542ms@13.8v/43.5psi

Did you change the crank table also?

No i did not touch the crank tables, from what i read that you keep that unchecked, Believe I tried it both ways and still nothing


left a few things that I have a Z32 mass air which I've changed and runs with no issue , rb25det turbo rebuilt by. pure turbos running stock boost, stock fuel pressure regulator,

adjusted the lateceny to 542, looking at other posts i see other brand injectors are adjusted to 800+ maybe that's the issue ?

Bigger injectors need crank table adjustment. You need to check values in this table (compare against factory ones) and then adjust until it cranks and starts throughout temperature range

Is the Z32 MAF genuine (ie not from ebay or cheap online shops). Has the ECU had K constant been adjusted so ECU is operating in the full range of load (TP) scales adjusted for the Z32 MAF?

About 800uS is normal, but you need to sort out scaling firstly and then fuel map adjustment afterwards

Z32 is a genuine maf,
which has been audjusted for full range load scales and i constant believe it was automatically adjusted and works fine with stock map.

i'm gonna give it a shot later with the cranking tables and see what happens, i'll keep you posted thank you !

Matt wrote:Bigger injectors need crank table adjustment. You need to check values in this table (compare against factory ones) and then adjust until it cranks and starts throughout temperature range

Is the Z32 MAF genuine (ie not from ebay or cheap online shops). Has the ECU had K constant been adjusted so ECU is operating in the full range of load (TP) scales adjusted for the Z32 MAF?

About 800uS is normal, but you need to sort out scaling firstly and then fuel map adjustment afterwards

I was able to get the car started with updating the latency, just gotta fine tune some things. I guess the latency i entered was way too low for the injectors. I will keep you posted. thank you for your help!!!

So as i stated for car started, just got a wideband it's running way too rich 11 afr, tried adjusting latency best i could get it was 12-13 afr but has car at 14,7 but wanted to die.. not sure where to look

ok so adjusted some options got the afr 14.7-14.8 @ idle

I adjusted the Injector latency to : 645us and the k constant to :322-329 seems to work.

The startup issue seems to have been resolved, Took for a test drive, pulls a lot harder than it has since the new injector install!

Just wanted some input on what you thought on these adjustments

I was able to get the car started with updating the latency, just gotta fine tune some things. I guess the latency i entered was way too low for the injectors

Only crank table is used for starting. Latency is only to adjust for injector dead time and really only affects idle

So as i stated for car started, just got a wideband it's running way too rich 11 afr, tried adjusting latency best i could get it was 12-13 afr but has car at 14,7 but wanted to die.. not sure where to look

Start reading our tuning guides. You are adjusting the wrong parameter if you want to fix overall mixtures

ok so adjusted some options got the afr 14.7-14.8 @ idle
I adjusted the Injector latency to : 645us and the k constant to :322-329 seems to work.
The startup issue seems to have been resolved, Took for a test drive, pulls a lot harder than it has since the new injector install!

Your base adjustments should be done on cruise (not idle). So get K/TIM in the right spot so you have 14.7:1 on cruise and then you can adjust the rest

ok i will go over the guide some more, starting to grasp this a tad better. thank u