Jump to content
SAU Community

Recommended Posts

I have a hcr32 gtst typem

rb20det with cooler, exhaust, locker, teins and a hicas lock.

My car has begun hunting, and after running the diagnostic tool, (which showed little,) cleaning the afm, tps and aac valve, and resetting the ecu, i am beggining to become confused and i am after suggestions as to why this could occur.

Does anyone know a 'normal' voltage or resistance for the AAC Valve? (as i beleive this is the source of the problem).

Also, when the fan (ie ac) is turned on, the idle drops from 1900 (way too high, but high enough for it not to hunt,) to about 1100 rpm. This is what leads me to beleive that it is the AAC Valve.

I have adjusted the idle, both at the AAC valve and the ecu, and it still idles way too high/ hunts.

Short of replacing all involved components (and my life savings at a local nissan dealership) what other suggestions do you have?

BTW, I have already searched, and the most common problems (TPS, AFM, AAC Valve etc) were dealt with

Edited by Mulkers
Link to comment
https://www.sau.com.au/forums/topic/140346-im-going-hunting/
Share on other sites

unplug the aac valve and see if the idle stabilizes. If it stalls adjust the idle screw until it will idle. Check for vacuum leaks (insert usual atmo bov/loose spring question here).

You could just have a faulty aac valve. By disconnecting power it cannot increase or reduce the amount of air the engine can breath. If the idle still hunts then it's something else, if it stabilizes then it's the valve.

  • 3 weeks later...

Stepper motors can have over 200 different positions... but O.T.

This is about the AAC Valve (I think,) I had a good look at that thread, and most inoformation was useful, but didn't solve the problem. What other reasons coudl there be for a unusually high idle?

All Nissan's use PWM 2 wire idle valves not stepper motors.

RB20s often size the cold idle valve open (Bimetal spring controled) and idle fast causing the over run fuel cut to hunt.Block this of and see if it stops the problem.This is not the idle speed valve remember but the warmup valve.

  • 1 month later...

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now


  • Similar Content

  • Latest Posts

    • Oh, also, forgot to add these photos I believe.
    • Thought i'd update on this. I was able to get in contact with Craig Lieberman and later on Darryl Alison (owner of Kaizo Industries). Darryl was able to help me verify that my car was in fact one of theirs and is helping me find more info on mine !
    • There's restrictor pills in the stock boost control hoses. That's how they set the amount that was bled off and hence the "high" boost setting. The usual mod in the day was to remove it and send the "high" boost setting up to about 14 psi.
    • Thanks Duncan, that's the best info I've read. Furthermore after learning about the PCM programming side controlling the factory boost solenoid, the purpose of the solenoid is to "bleed" boost when pin 25 is earthed, thus allowing spring pressure in the wastegate actuator to overcome diaphragm boost pressure, thus closing or reducing the position of the wastegate flap creating more boost as the turbo is able to spin faster. It's pretty cool to see a designated Pill to do exactly this, would have liked to have seen it with a tiny filter over the end for those moments in vacuum.  The constant bleed pill has now been removed completely from the system and solenoid boost control has been restored once again.   Case closed 😂
    • The wideband reading is meaningless if it's not running. Why are you using shitty old sidefeeds on any engine, let alone a Neo? What manifold and fuel rail are you using to achieve that? Beyond that, can't help you with AEM stuff as I've never been their ECU/CAS combo.
×
×
  • Create New...