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Don't know where to begin Startup issues

Posted: Fri Jun 10, 2022 6:29 am
by Xxmarcusrxx
LIttle background:

Before Rebuild:
stock internals aa501mt ecu
z32 maf blowthrough
gt3571r turbo
FAST 30857-8 85 lb/hr injectors ( I think this is what i have, couldn't find a record of purchase)
255 walbro fuel pump
base fuel pressure (?)
Innovate Wideband
** Boost sensor was connected but not sure if i connected it to vacuum)
After Rebuild:

Rb25det Neo aa501mt ecu
ls2 coils
Just rebuilt. Full forged internals
Tomei poncams 262 9.15
Bigger t4 turbo
525 fuel pump
HPX n1 Maf Blowthrough
3in intercooler piping
FAST 30857-8 85 lb/hr injectors
Base fuel pressure 43psi
Innovate wideband
Rebuilt Cas by taking apart and replacing bearings
** Boost sensor not connected **

with the original base tune, car ran and started fine with no for seeable problems at 14psi till no compression in #1. Rebuilt the motor, after 10 years, used the same tune after changing maf to hpx 3in, no start. Got fuel pressure, spark (by turning the cas by hand) fuel in cylinders and air.

Changed map to stock used the "change maf" feature, and injector resize. Lowered crank enrichment and it started! By started i mean Putters to a quick death. Can't keep it alive long enough to get a good log. I have to constantly tap the gas pedal to keep it alive. Wideband flips quickly from lean to rich then lean again, car dies and the wideband takes so long to start reading I can't get a good look at it while trying to keep the car alive. Did notice while the car was running ( for the 10 seconds at a time) exhaust manifold was really hot, almost too hot? can't set the base timing because the car won't idle at all. Tried sliding K constant in either direction with no change.

Here both the original (before the rebuild) map and the map that makes the car start. with a log of the seconds it was running if it helps at all.

Any help/ ideas would be much appreciated.

Re: Don't know where to begin Startup issues

Posted: Fri Jun 10, 2022 12:44 pm
by Xxmarcusrxx
So I reviewed my logs I believe my aac originally was plumbed (incorrectly) into the intake system. Now it is capped off. I never have an IAC (air regulator) and didn't know i needed it. I see the AAC values spiking and from what ive read AAC "Adjusts duty cycle along with timing to achieve target RPM at idle." I see my timing jumps from 10 to 40 while trying to keep it going. Until i order the IAC Should I just unplug the IACV? I feel like this could be the issue. It's too late to try but i'll update tomorrow.

Re: Don't know where to begin Startup issues

Posted: Thu Jun 16, 2022 8:59 am
by Matt
original tune vs AA501 (non-FP)

Have you disabled the ABS/TCS in this ECU? One of the ABS/TCS is still ticked, so would suggest unticking that (DTC Filter 1)

Idle speed, Neutral, TPS idle, O2 RHS (doesn't exist), ECCS relay (not read), injector circuit are ticked but are not in the factory base image. Unsure of side effects here

You have knock maps in this ECU and changes to them, but feedback Knock analysis, and knock sensor 1/2 are disabled

O2 voltage lean is showing 400. This will likely result in feedback more reading on the rich side, and start leaning out your tune. Why was this changed?

Re: Don't know where to begin Startup issues

Posted: Thu Jun 16, 2022 9:01 am
by Matt
ls2 coils
Original showed dwell changes. So maybe you had Ls2 coils in then?

Re: Don't know where to begin Startup issues

Posted: Thu Jun 16, 2022 9:05 am
by Matt
So comparing possible against original

Fuel and ignition load scales don't look right at all. See fuel - its maxed out 255 and the ignition load scale is flat from 132. This wont work at all

Then your fuel map adds more fuel (likely to compensate for the flat scalers)

Then the boost sensor table got back to normal

Re: Don't know where to begin Startup issues

Posted: Thu Jun 16, 2022 9:13 am
by Matt
HPX table is also set to 'max load' and this might contribute to needing different load scales
You also need your boost sensor hooked up properly - Read through the NEO tuning guide on our website for info covering this

To fix this
Put your boost sensor back connected in correct position

1. Use original tune
2. Change MAF from Z32 to HPX (Z32 MAF scales)
3. I've put temp and RPM enrichment back to factory
4. Put O2 volt lean and temp to factory
5. Fixed up VCT RPM and cut (these were backwards?!)
6. Disabled Use TPS2 sensor (FB switch 2)
7. Set TP cut table and boost sensor max voltage to top. Also limit counters to max (covered in NEO tuning guide)
8. Left fuel map and load scales how it was (since injectors have not changed)

Re: Don't know where to begin Startup issues

Posted: Thu Jun 16, 2022 9:14 am
by Matt
So try that attached out and see how that goes