Yeah, I was gonna say you have to be over a certain load and rpm before the mivec maps are used..... you can play around with the settings all you want at idle, but they won't be used. I don't know the exact point where they become "active" but IIRC it was around 1,500 rpm or so... based on log from my old GSR.

 

That's weird, on the evo 9 they are affected on idle. I will increase the overlap at idle and see if anything will change (the idle should be very bad in case the mivec tables are working on this rpm)

 

yeah - when doing my live tuning test I had to hold the rpm's to about 1500rpm for the live mivec changes to take affect

I will work on a mod to get idle-mivec working

 

It sounds like you missed an RPM table. What ROM ID are you running?

 

I wonder if this is a safety feature... possibly related to there not being enough oil pressure at idle to properly actuate them?

 

That was exactly my thought when i noticed it.

 

could be I guess..

although the system already has DTC's for when CAM advance/retard is too far from requested...

I guess I will defeat the idle limit, then try changing the timing and see what happens..

I dont think I can cause mechanical issues??!?

 

I have a related idle issue after swapping in a Boomba 3" Throttlebody. Basically after I installed it or if I reset the ECU, the car literally dies and won't idle at all. I think it is due to not enough air getting to the engine as holding down the throttle slightly will prevent it from stalling. It must actually seal "too well" and without physically taking it out and removing some material it will be a pain.

All of my idle tables are set to 850+ and it didn't really help. Timing advance is 12* instead of 10* which helped smooth things out a bit bit really didn't help. The car will eventually learn the idle but if you happen to reset the ECU before a race, stalling at the line isn't my idea of fun.

I ended up adding in a few TPS percent in the 500 - 1500 RPM range at the left most column in the Throttle tables as a work around for now. Seems to be enough to keep it from completely dying until it learns idle better. If you log how much Actual Pedal percent you need to just barely keep idle to your set point, that should be the max value you add there.

 

^ So we need to find the idle initial part..

Let me have a look

Although I would have thought the same throttle angle on the stock TB would equate to roughly the same airflow as the same angle on the Boomba TB...

and thus you should have a good idle..

unless the boomba TB closes more than the stock piece...

 

12 instead of 10 ins't much... you can go as much as 18 and still get better idle for each deg you add...

I dunno why but i tried messing with the throttle maps, but it didnt yield any result... logging the tps still showed the same value regardless of what i put in the the maps...

Eventually had to raise the idle to 1000rpm and idle timing at 17deg... now idle is good

 

well that timing might be right for those cams..

with my live tuning, dialing in the ignition advance was really easy, and you can "hear" how each degree makes a difference, after a while it becomes laboured, so you can back it off a bit

 

So how much timing did you run at idle?

 

S2's will most definitely need some major Mivec adjustments on the X, however the idle really shouldn't be all that bad.. PM me if you can't get it sorted.

 

I do think the Boomba closes more than stock or just seals better, I entered 3% last night where the left most column was 0% and reset the trims... idles like a champ now right after reset. Just did a horizontal interpolation so that pushing the throttle slightly doesn't lower TPS and then go up again and it works perfectly. For those playing, make sure the main tables #3 and #4 are altered, and you may as well alter #1, #2, & #5 even though they are the cold start tables.

This trick could help cams that are not flowing enough air with a closed throttle plate somehow, although I think advancing timing a bit and setting idle tables to 850 or 900 rpm is the better first approach.

 

because I am subscribed to so many threads its really easy to spot spam haha