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Why is my IAM at 15?

4K views 42 replies 5 participants last post by  Bahaa425 
#1 ·
Hey guys, been looking at my learning view on my 02 wrx and noticed my iam is at 15 and i have some knock. Could you all look at this and tell me what you suggest i do?

Car
02 wrx
jdm ej205
catless uppipe, midpipe, downpipe,
spt catback
spt cai
silicone inlet
PNP td04 (mirrored finish)
xpt stage 2 tune

Heres the snapshot of my learning view after 50 miles on ecu reset

https://drive.google.com/file/d/0B0KjInu310FjR1VzaFhodi1zWWs/view?usp=sharing
 
#7 ·
Interesting, I always though negative number meant the car wasn't recovering the measured are because of a boost leak, I didn't think pre turbo would cause rich condition. I'll go through and start putting clamps on all my connections to the silicone inlet, those hoses don't feel too air tight
 
#8 ·
Stock injectors? You claim to have a "JDM EJ205." Does this include the fuel assembly? TGVs?

I find it interesting the learning is pretty even across the airflow bins.

FYR, negative learning means the ECU is removing fuel, not adding fuel. Therefore, it is unlikely that a vac leak is the culprit.
 
#22 ·
Honestly your response is unfortunate, I do wish the best for you and hope it turns out well.

I appreciate the drive to learn, but you're reaching too far ATM; I would recommend easing in with more simple adjustments if that's something you'd like to do.

As mentioned, adjusting the wastegate arm is not the appropriate way to adjust boost since this is literally varying the position of the wastegate flapper. What you perceived as a "lower boost target" is indeed a mechanical failure of the flapper to build boost appropriately. The ECU and boost controller is still attempting to target the 17 PSI, but this is not possible due to the flapper allowing air to bypass the turbine. Yes, this is what the wastegate does in proper operation, but since the flapper is open (when it should not be open), you will kill your system's ability to build boost leading to lag and poor transient response. I suggest you read a bit about electronic boost control.
 
#23 ·
So why don't we forget about boost to start. The whole "fueling isn't right, so let's try fixing the boost" approach will only lead to terrible things. Your ECU may be defaulting to another fueling map or cutting boost if things aren't right. Gotta go step by step.

Always get your fueling dialed in at low loads, first. Then extrapolate the changes. Move on to medium loads. Now extrapolate it again. Then heavy loads. You only proceed as each step is near perfect. If it's not, try again. If your low load fueling isn't stable, you near certainly have a mechanical issue (e.g. leak).

So let me say that again, fix your fueling issue. There is no need to worry about boost until your fueling is looking great.

Now, on the boost issue, sometimes you do have to tighten the wastegate arm on certain turbos. It's an 'as needed' thing. You should be controlling boost via modulating pressure 'sent' to the wastegate actuator. Check out my link below - I think its part 2. I don't feel like typing the whole post up.

http://www.clubwrx.net/forums/tunin...t-2-turbocharger-101-basic-boost-control.html
 
#25 ·
Thank you, last night coming home i noticed idle was off and my boost gauge died completely, come to find that my gauge hose had snapped in half. Ive replaced the hose and idle is back to normal. Im interested to see if that could have been A cause of some of my problems.
 
#29 ·
Clean your MAF.

The learning in the D cel is the one that matters for WOT and for high load. It is 0, so there is no fuel being pulled in the range that really matters. Boost leaks don't go away at higher load, they get bigger. So that fuel trim pattern is not supported by a boost leak or a vacuum leak. So I'm thinking MAF dirty or O2 sensor getting screwy, maybe exhaust leak. Or just bad scaling given it is a hybrid of sorts with the intake.

Why are we looking at learning view and not a log?? All I see is low end knock learning, but the table would have cleared when the IAM dropped. What does a WOT log show? I've seen IAM it drop from someone lugging up a hill here recently (low RPM, low throttle, 5th gear (WTF?). Or it really could just be crap gas.

For this complex a situation I'd install a wideband. Well, I did and I'm only stage II, so yeah, why not?
 
#32 ·
Tightening the wastegate arm against the spring just increases the pre-load. It can be useful if you aren't hitting boost target by a couple psi as indicated. Beyond a couple or three turns I'd quit and look for another way to hit the target (or make a more reasonable target for the setup). Tightening it to increase the target though is not productive. I agree though, that you don't want to hit the target really until you get stuff sorted better, and that not making the target is not what is up with your fueling situation at all. It is just helping prevent knock at high loads for now.
 
#41 ·
FWIW, I clean mine with direct blasts. I can't see it harming it at all compared to indirect blasts, but you never know.
 
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