Nistune Forums

I put in the Injector Dynamics 1000cc injectors and I can't get the car to start now. I went into nistune, changed the injector size from 275 to 1000, set the latency to 1325US as per the datasheet with my injectors, and turned of the o2 flag and then burnt the changes to the daughterboard. This is on a S14 KA24DE. It changed the K-Constant from 259 to 70. If I change the injector size in nistune back to 275cc, the car will start up, just runs horrible due to me having the 1000cc injectors. I'm unable to check my fuel pressure when cranking the motor because the gauge is in the engine bay, but when I prime the pump (ignition on, engine off) the gauge on the regulator goes to about 50psi. I still have the stock fuel pump, but I figured it should provide enough for at least the engine to start and as I mentioned, if I lower the injector size, thus increasing the multiplier, it will start, just runs rough. I knoww the injector change is just for a rough estimation K-Constant, but shouldn't it be enough to start the engine? Any advice on troubleshooting this?

Why do you have 1000cc injectors on a DE ? Can't imagine any reason unless its a DE+T ?

50PSI seems a bit high for rail pressure too unless you've deliberately set it high. Should be low 40's if you want to have 'normal' rail pressure.

When you use the resize injector function make sure the "change crank tables" box is UNticked and try starting her up, see if that helps.

Yes, it is turboed. I just have the turbo turned off right now to make sure I get it running stable without any boost.

I redid the "resizing" without the crank adjustments (after reverting back to stock) and now it starts, but when it starts the AFR is 10.1 and then it goes up to 17.1 very quickly and stalls. It happens so quickly I can't get a log from nistune (It stalls by the time I click connect to consult).

check you don't have an air leak around the injectors you just installed.

may have a rubber o'ring seal not seated properly causing air leak and hence the afr shooting up and then stalling out.

I swapped out the injectors for a different set. The one's in there now are 65lb / hr. So I set them to 683cc. After the change I was able to get log for the few seconds that it ran. It is now starting at around 12 afr and then climbing to 17. I have attached the log. Pushing in the throttle makes it worse so I'm assuming it's not getting enough fuel.

I changed back to the stock injectors and stock Fuel Pressure Regulator and loaded the stock S14_KA24DE_MT image from the nistune rom pack and the issue still exists. This leads me to believe that the issue either lies in one of the following:

XCESSIVE Intake Manifold
Q45 Throttle Body
Q45 TPS
IACV Removal
JGS Brake Booster Vaccum Block
PVC Dumped to atmosphere (Hose from pcv valve to ground)

How can it regulate any idle (cold or warm) with no IACV ?

Although idle isn't being regulated, it should run with throttle. As soon as I hit the gas pedal, it stalls out. This is why I am thinking it's not getting any fuel. As soon as I open the throttle, more air is going through, but the fuel just doesn't seem like it's there. If the issue was with the AIC valve then this shouldn't happen, right? Could the TPS cause this issue though?

I may try to reassemble the old manifold and old throttle body and see if that corrects the issue. I just hate to take the fuel system off again take the manifold off too.

are there any DTC's? maybe MAF?

Had a Q45MAF a few weeks back where two of the 3 wires were snapped in the rubber boot.
naturally it was purchased as a 'used' working MAF with low km's.

The MAF is still the stock S14 MAF and it worked fine 2 months ago. There was 1 ECU message, but I forget what it was. I will try to capture it again.

Here's the output

ECU Messages:
[25] DTC IDLE SPEED CONTROL VALV (Starts=0)
[A5] DTC ERGC SOLNOID (Starts=0)

Flags in Red:
Neutral sw
Fuel pump rly (When car is running)
TPS idle (unless I push the throttle)

Flags in Grey:
Pres reg sol
w/gate sol
FICD sol
EGT sol

Could be a leak from the manifold. Was it the bolt on kit from Xcessive?

With the big TB it may have become a little touchy between TB closed and when it opens. Might be worth playing around with the TPS so that you lose the "TPS Closed" flag as soon as the TB is cracked. Just a thought...

PL

BlueRB240 wrote:Could be a leak from the manifold. Was it the bolt on kit from Xcessive?

Yes, it is the XCESSIVE KA24DE Intake Manifold Kit with the Q45 Flange pre-welded.

PL wrote:With the big TB it may have become a little touchy between TB closed and when it opens. Might be worth playing around with the TPS so that you lose the "TPS Closed" flag as soon as the TB is cracked. Just a thought...

PL

I may look into that as well. I may a lot of changes at once, so to narrow down the cause I swapped out the intake manifold for the original one and just ordered a silicon coupler needed to hookup the intercooler cold pipe. Once it comes in I will put that on and try to start it again. In the meantime, I also sent an email to Rich @ XCESSIVE to see if I can get just the plenum with the stock KA TB flange. I want to get it running, even if it's with the OEM manifold and then add piece by piece so I know exactly what is causing the issue without making too many changes.