So I've been having an issue where my idle is right around 11.1-11.4 and I'd love to get it up around 13.0.

Other than being excessively rich its a very stable idle between 800 and 1000 depending on AAS position.

I know most people change the lag settings but since I'm still running 550's that seems more like a work around.

I've played with the water temp correction table and by taking it down to about .750 at 80c I got it into the 12's but this causes the entire map to lean out. (I'll need to retune the map anyway not a problem)

I also played around with changing the base fuel pressure but I had to take it far too low, under 20psi, to get it to 13's.

Mod list.
PFC
Datalogit
550/1680 injectors
FJO Injector driver (wired for both prim/secon)
HKS Twinpower
Intake
SMIC
Exhaust w/cat
no airpump

attached is a zip with the latest map and some logs (some junk decel data)



So what's the best way to lean it out?
Should I just resign myself to changing the lag times?

Edit: ICV has been removed and idle control and o2-feedback are turned off.

 

Running low fuel pressure for idle will just cause fuel problems under boost, a bad thing to do!
After a PFC is set up, and with the CORRECT injector setup; the first tuning before anything else is HOT idle.

If you are running an air pump, ISC, and O2 FB, you really can not get idle leaner as the SYSTEMS are controlling fuel, timing, and air.

If you turn off O2 FB with an air pump, or remove the AP which makes you have to turn off O2 FB; then you can control the fuel better. But if the ISC is controlling revs, it forces you to use the timing it wants. And this timing is not what you see in the IGL/IGT tables. It is what you see in monitor mode. It is retarded timing. Low timing and rich fuel and low air flow makes the engine idle very low rpm and smooth, but rich.

Turn off the ISC by setting the three revs to 0. Now the engine will idle in pure manual mode. This allows you to adjust, air, fuel, and timing for the leanest possible choice. But this requires you to make seasonal changes and run higher revs to be smooth and to keep the engine from dying when the AC is on.

Many including me do this to help keep the plugs/engine cleaner. I even run up to 16.5 AFR at higher cruise speed above 45 mph.

 

What is the "CORRECT" injector setup? I've changed settings 5 to reflect 550/1680.

I've been reading other threads about this problem and it sounded like its not possible to lean out cells in the idle region beyond a certain amount. I've tried using the commander/FC-Edit to lean it out but it hasn't gotten me anywhere which is why I've tried those other methods.

Are you saying by setting the three idles to zero that I'll be able to lean out the idle region or does that only allow me to change the timing? I'm not really worried about timing because I haven't been able to get my A/F low enough to worry about that part yet.

 

Did you adjust the idle cells in the inj map? I assume you did but you didn't say so. Or how about adjusting the pim table at 8k. I recently put my isc back on and get the best idle with ign control on, after trying manual control and all kinds of stuff, afr right around 13.

 

Setting the 3 idle values allows you to control timing at idle after its warmed up, but I have a smoother idle with those idle values set to a desired idle rpm, not 0.

 

Others problems:
Your timing split is very bad.
Turn off the IGN vs Water Cool retard to 0.


Check your TPS VOLTAGES.

 

Did you cap off the injector atomization port on the manifold?

 

I haven't changed (or even looked at my split until last night) and I agree, very bad. Is it better to run aggressive split with retarded leading or more advanced (reasonably) leading with more split?

When I last checked TPS V I remember them being within spec. I believe it was around .53v closed.

They aren't capped off but I think I tee'd them together and didn't hook them up to anything when I went simplified sequential. One more thing I could check.

I don't have much time to work on the car during the week so I haven't made much progress with my idle.
But I will add that I'm seeing 11.x A/F when injector duty cycle is right around 4% and I remember reading this in a thread somewhere:

This was in reference to using 850's as primaries, but I'm starting to wonder if by getting my 550's cleaned and flow checked and using the FJO driver to run them might have changed their lag time? Does this even make sense or am I off my rocker?

 

Your timing maps are the default maps that came with the PFC. I wouldn't consider them very bad, just cause I ran with them for a few years running alot of boost and going fast. But I recently changed them. Just to add some safety you could change the split to 10 or 12 in the boost rows, like where it goes below 10. This is what I did to mine, and left the leading map mostly the same, just very minor changes.

If you run race gas then you can run a little more leading and split suggested above, that's what I did at the drag strip last time and went faster. It's safer to run more split and retarded leading timing but could make more power with a little more advance leading timing, that's my understanding anyway.

 

what is the perfect idle? my idle is at 12.5-12.8 hot

a bit leaner cold , But my friend's idles are all at around 14.7 -15.0 weather it be an fd , or a mazda speed 3 , or a 240 , everyone has their idles at 14.7 .. I read somewhere on these forums that the target idle for the FD should be 12.5 so I adjusted it to that . Now I'm a bit skeptical is this the correct idle or are they correct ?

I read 12.5 was good because idle fluctuates alot .

 

12.5 - 13 is good, if its much leaner than that then the idle won't be smooth.

 

IC thank you

 

Sounds like you should leave it alone.

 

just to add insult to injury what injector duty should I be at ?

a little bit on my setup ,

PFC
550/1300 injectors

rising rate begi FPR ( jsut added this yesterday )

My car was going lean up top even though on the power FC I had it adjusted to be 120% the PPIM VOLT to 120% above 4k RPMS , which is where the car was going lean under boost .

BUT it would go into the 17's up there . and my injector duty was at 80% and it was only at 10 PSI .

so I know something had to be wrong as this was a sudden thing one day things were fine 10/af under wot then all of a sudden lean .

I've changed everything in the fuel system save the fuel pulsation damper which I smell for and havent seen leak .

NOW what does all this have to do with my idle ( sorry for the rant )

I added the new FPR thinking this may be the case of what went wrong

I adjusted it a bit , and my a/f under boost went a bit richer into the 14's ( stil llean )

BUT my idles also went richer at 4% which is what they have always been and with 4% it used to be at 12.8 now the car is into the 11's

I adjusted it and at 3.4% its just now at 11.8-12.0 a/f so before I continue to adjust the idle , I want to know if thats normal for the fuel setup I'm running if its ok to keep adjusting and i'm getting a fuel pressure gauge this week to fine tune things