RomRaider

Hi Romraider Team,

I have talked to many of the team members individually but havent compiled a full list of parameters that have to be met in order for AVCS to reset itself and eventually Activate.

The reason behind getting these full conditions is i have had multiple high mileage STI/WRX/LEGACYGT that have come through lately where im tuning like normal and then the AVCS resets but never goes to the commanded values. at first glance i do the normal thing which is put the rom back on you started with to see if it starts working again, thinking its a alpha definition that isnt working right... but in all cases thats not the case... and it still doesnt work. Luckily in all cases i had AVCS working right but havent seen the cars since and say they work great.... I will have one car back soon to finish this and end the request once and for all. So below are the minimum requirements that need to be met in order for avcs to work

Idle: Below 1050rpm
Coolant: above 70C 158F~
Must go into 8 mode from warmup of 7.
IAM = cant be 0
CEL = cant be flashing/on
cruise control light cant be flashing
NPS (Neutral Position Switch)
Fuel Pump Duty @ lowest setting
Speed = 0MPH/KPH

What else is there i should be looking at?? IAT? / Warmup tables for a certain period of time? hot start in those cases have to run a minimum condition...

Are there tops to these tables... meaning if it starts up at 215degrees coolant it doesnt work..... I cant figure out the last piece to the puzzle.

I did hear you have to sit for at least a minute... but i have tested that too, most of the time going from 7-8 mode takes at least a minute anyways.

So recap, I see 7-8 mode, i see the AVCS set to 0 and then nothing works even brake boosting to make it turn on...

Did i miss something?

Vehicle speed check too. Don't remember some others. There's a lot that nobody knows. Haven't gone through it yet. It's planned for my future if I ever get time.

IAM does not need to be on 1.000 or 16 etc, seen plenty function on factory IAM value straight up

Easy one? Log Fuel Pump duty, after a flash and during initial idle, wait for the Fuel Pump duty to drop from 100% to 33.3%(or whatever value you changed lowest duty to) and then your set to go.

What I do is after a reflash, I make the car idle and wait for afr sensor ohms to stabilize from 255. Still on idle, I press on the pedal quickly to see any movement in the avcs. If I run the car before this, sometimes avcs will go on without working until after the next ignition off and on cycle. Issue as well is the condition of the ocv and cam timing sensor.

NPS (Neutral Position Switch) is one of conditions for sure.

Im still fighting a car that wont do it... the only thing i can think of is that the NPS is broken...

Off to test in my driveway

not the NPS....

im stuck as to where to go from here... Out tuning, randomly stopped working. went back to the stock rom, still not working...

Take the sensors out? wth....


--Update ---

Took both the solenoids out and cleaned them. Still nothing...

So the AVCS resets to 0 then never commands it to anything. great.

Did you log NPS sensor value as graph?

When I had problems with AVCS's, looking at NPS variable didnt show nothing special, but when logging it was obvious that NPS is losing signal thus turning AVCS on and off during driving in gear. New NPS solved the problem for me.


And I believe it should be: Speed != 0MPH/KPH

I tested the NPS in the driveway and it seemed good. BUT i didnt try driving it... crap.. now the cars gone.

Time to Resurrect this thread. I've been experiencing this exact same issue with my V9 EJ207. Ive already replaced the NPS with A 06/07 USDM STI(0 in gear 1 in Nuetral) in the last 2 weeks, started with a fresh non inverted NPS rom. Fresh oil, subaru filter. made sure the AVCS Cloggers were not present. I'm starting to think that this is a ROM issue or a glitch in the ECU.

I've loaded Carberry 4.2 to basically Dump and refresh the memory blocks on the ECU and reload the stock rom, it works a little more consistently afterwards for a few ignition cycles but it will just go back to not working

I'm all ears if anyone has some advice


Devin


V9 EJ207, VF37
Zero Sports Downpipe
Genome STI Axle over
Okada Coils
AEM 340LPH Fuel pump

Just a quick update:

I've come to the conclusion that my intermittent non functioning AVCS has to do with changing the fuel pump duty. whether this is the direct cause/effect from something like voltage drop off during or shortly after starting. whenever I change the idle Pump duty I may or may not have functioning AVCS until I cycle the ignition at least once after a reflash. AVCS almost never works if I reset the ECU from RR logger, I have to flash a different version of my rom and then reflash to the newest rom to get the AVCS to operate properly.