I'm about to kill someone.... CA18 HELP REQUIRED

zrated · Post by **zrated** » Thu Dec 11, 2008 6:22 pm

Sorry to be blunt but I've spent all day on this bucket of you-know-what and am getting absolutely nowhere. I'm almost at the stage where I'm going to throw my laptop, nistune and everything associated with tuning in the bin.

Here is the car.
S13 CA18DET
555cc Nismo Injectors (Pink)
J30 Airflow Meter?? (Purple Sticker 22680-16V00)
China Turbo, external gate, etc, etc (all the stuff you dont need to know)

Board: Nistune Type 1 Board
Address File: S13/RS13 (CA18DET)[16K REV3+BOARD] (Version 4)
Binary File:S13_CA18DET_36F00_MEC-D003E2_JDM_MT

KValue: 192
Injection Latency: 550
Other Notes: K Val, Load Scales, TTP Min/Max all modified via the nistune tools (resize injector tool and change airflow meter tool). Latency was left the same.

Here's the problems

1. Super rich at idle, around 11:1. A higher latency results in a richer mixture (wtf??). A lower latency results in a slightly leaner mixture (12:1) however the idle is shithouse and the car often stalls.

2. Car will stall under hard decelleration (rev to 5-6k and let close). Revs will drop to around 400rpm, then it hesitates and stalls.

3. Car is leaning out at around 4500rpm. No matter how much fuel is put in, it still leans out (from a nice 11.5:1 up to around 15:1).

What I've done
I've done just about everything, i've checked fuel pressure, set base timing, check for vacuum leaks, installed new plugs, made sure throttle body is nice and clean, etc, etc.

Am I missing something?

PLEASE HELP, PLEASE PLEASE PLEASE! I'm going crazy and beginning to hate nistune.

lyckaon · Post by **lyckaon** » Thu Dec 11, 2008 7:36 pm

You could try to plug the fuel pressure regulator directly to the intake manifold and bypass the hot start solenoide!

Legionnaire · Post by **Legionnaire** » Fri Dec 12, 2008 5:40 am

The very first thing i thought of was major vacuum/boost leak, i.e. from somewhere between MAF and the engine. I've had this one with the stock SMIC - rubber hose to a throttle body used to slip off the hard plastic pipe above radiator. But you said that you already checked it.

the second (and as obvious as above) is - your fuel pressure regulator does not recieve proper pressure reference signal from your intake mani. Have you checked your fuel pressure only at idle, or throughout entire rev range?

the third - isn't that issue related somehow to the wierd way that CA18 ecu uses to read MAF signal (and what it expects from it)? Or, maybe it is as simple as a dodgy/dead MAF sensor?

those are my thoughts so far

TSL · Post by **TSL** » Fri Dec 12, 2008 11:04 am

Never had problems tuning ca18det with nistune.

Maybe upload your tune so we can at least have a look at what you might have done?

zrated · Post by **zrated** » Fri Dec 12, 2008 12:05 pm

Ok i just did another boost leak test and it seems as though one vac line dropped off.... I've fixed it up and the car doesn't stall when the revs drop (hooray) but it's still leaning out at high rpm.

I loaded up the newest nistune software and the knock fuel map is being used, (it's coloured red in the list)... I gather that's why changing the fuel in the normal fuel map isn't doing anything...

Why would it be accessing the knock fuel map?

I've had a look for error codes and nothing is showing up, not even the normal 'OK' message.???

zrated · Post by **zrated** » Fri Dec 12, 2008 12:33 pm

i've attached the binary, it's not very 'tuned' at the moment... you can see that i've just thrown a heap of fuel at the top end to see if the afr's change on the dyno, but that's about all i've touched, except for the ttp min (slightly) and the usual limiters, etc.

Can someone tell me how to change the ttp min/max properly?? What does it affect? Also how do you tune the decel fuel cut, etc? A more detailed explanation would be good

Any input on my problem would be appreciated.

zrated · Post by **zrated** » Fri Dec 12, 2008 1:20 pm

something bloody strange is going on, if you download the map and have a look, the normal fuel map has gone freaking... 14.7 all over the bottom half of the map... i'm confused!!!

lyckaon · Post by **lyckaon** » Fri Dec 12, 2008 6:18 pm

I think the TTP min and TTP max in the last CA18DET 128bits address file are inverted...

And your TTP max is too small...

I attach my addres file.

Matt · Post by **Matt** » Sat Dec 13, 2008 12:44 am

yes we looked into TTP min/max and they were found to be the wrong way around