With the Adaptronic Forums down, I didn't really have a good reference for learning how to set up idle. I dug through the base maps to figure out why I was having so much trouble. I have figured out most of it for my N/A 13B with quad ITBs and figured I would share so that a) I don't forget and b) perhaps someone else might need this info. The issue I have is that my REPU is old and the transmission or speedometer does not have a speed sensor. The Adaptronic 440d doesn't really like this and was doing all sorts of weird things thinking my car was stationary when in fact I was in gear and driving down the road.

The symptom was that the ECU tried to go into idle whenever the throttle was closed, it would cut the timing by 10 degrees in an attempt to pull the RPMs down to the correct idle speed, the motor would sputter and AFRs would be all over the place. The trick, which I discovered in the RX8 select basemap, is to override the conditions for closed throttle.

On Aux Out Tab...
1) Set AUX 12 to Inverted Throttle Position 2/2 (flag will be true if throttle is below 2% from TPS, accounts for any stickiness or margin for error in the TPS but you can set it to 1%)
2) Set AUX 13 to Inverted RPM 1200/1300 (flag will be true when RPMs drop below 1300, will switch back to false as RPMs climb over 1200, set these appropriately above your target idle)
3) Red LED to AND 12/13 (flag will be true if both above conditions are met)
On Digital Input Tab...
4) Set Dig Input 12 to none
5) Set Dig Input 13 to none
6) Set Dig Input 14 to closed throttle act high (this will override normal closed throttle which is usually derived from Analog Calibration tab)
On Idle Tab
7) Make sure "Always do D on throttle-off" is checked

Monitor the ECU flags and you should see that the closed throttle flag should never be marked true unless your new conditions are met.

If you have an idle control valve (I do) the base settings need to be set in open loop. I did this by setting it to full open with a cold engine and adjusting until the idle was correct, and then as the speed began to creep up, I would check the temp and lower the value. I ran through a full warm up cycle and also had to make some changes to the temp enrichment table too. That got me close to where I needed to be.

The next step for me is to figure out the correct closed loop idle control PID settings. I don't think the ones in the RX8 select file are correct. I've tried a few different values but nothing seems to work perfectly. Right now I have a situation where the RPMs will drop to 600 or so then bounce back up, but sometimes it works perfectly. I remember reading one of Andy's blog posts (or maybe it was on the forum) where he talked about changing settings up and down...but I can't find it, and I do recall the post never mentioned where to actually start. All 0s? All 1s? One post said not to use the differential, another said set it to 1. All i know is that what I have no is not working. When I flip the lights on the idle drops with load from the alternator, and it should be able to step the idle back up...but that's not happening. When the motor is still warming up, the alternator will almost stall the engine.

 

I'm assuming u have a remote IAC valve with small hoses feeding air to the engine. Are the hoses going to the intake manifold or throttle body? I have a 98 Ford Taurus iac valve that I tapped to fit 3/8's fittings. I dont really want to drill and tap my throttle body. So I was going to drill and tap the intake manifold as close to the tb as I can. The Taurus valve is a 2 wire stepper motor iac valve. What iac valve are u using?

 

I didn't have any luck with the 2-wire ford type valve. I don't claim to be an expert but here's what happened when I tried to use it. I went through a few different vacuum line setups but the valve never seemed to close. I think it is supposed to shut as air passes through, and the solenoid is used to pop it back open. However, my motor just wasn't drawing enough vacuum to shut it.

I later switched to a Bosch 3 pin style valve and that gave me full control over how much it was open regardless of vacuum signal.

Since I have quads, I had to connect it to a manifold and distribute the air to each of the throttle bodies. The air enters through the idle screw ports on the Jenvey throttle bodies which is directly in line with the injectors. The location isn't important related to the throttle body, but it should be at or before the injectors.

 

My efi hardware throttle body doesnt come with idle screws. But sense I'm only using two of the four injectors. Because of the secondary injection timing on the adaptronic select not being adjustable. My primary injectors (750cc) are big enough now to run just two injectors. I need figure out a way to attach the hoses to the injector holes. I have seen plugs that I might be able to drill and tap a hole. Then thread a nipple into. Dont really want to thread the actual injector hole on the throttle body. Do you have a part number for that Bosch iac valve? Or what car uses them? Where did u get the manifold for it? I've seen them for jeep iac valves on DIY megasquirt website.

 

You can just search for "Bosch Idle Valve". The one I got was for a BMW but there are a few different ones depending on how you plan to mount it. Mine is pictured left below.



Since I have quads, I needed split 4 ways, and the parts that came with my Miata Jenvey throttle body kit worked fine. The supplied nipples replaced the idle screws. I'm sure any manifold, or in your case just a T connector should work.

 

I have no idle screws. Which makes it hard to get the air in above the fuel injectors. I think I will just drill a tap my own holes. I have some 12- 24 or 1/4 inch pieces of all thread that I drilled a hole through on a lathe at work. I'll use that as my nipple for the hoses. Did the same for the map sensor on the manifold. Ecu settings look pretty straight forward.