AEM Infinity struggling to reduce idle speed

Hi all,

Working on a built evo x that has a large 82mm throttle body. Car recently got a brand new ported head with oversized valves and now I cannot get it to idle at a normal RPM.

Things I've tried:

I've adjusted the ign trim table to take out a maximim of 18 degrees, and that really seemed to help. Not sure how much lower I can keep going.

The idle base position table seems to not do anything at all. I keep reducing it, and the idle does not respond what so ever.

I've increased the idle feedback parameter to take out a maximum of 10%, but that doesn't really seem to do anything either. I've attached a few screenshots incase anyone has some suggestions or wants to take a look.

Essentially the lowest I can get it to idle is 1300-1400rpm

Can you close the throttle more? It's indicating 4.4% -- is the linkage sticking, throttle stop just set too high?

Hi David!

So I've been working on this a few hours and I redid the entire DBW setup and was able to get the throttle to as little as 1.2% opening! Still, the idle is around 1400rpm.

I also noticed, if I rev up the engine and immediately let off, the RPMs keep on climbing, even though in the log I can see the TB is closed. As of this current moment I am checking for a vacuum leak between the head and manifold or the manifold and TB. I have a feeling that might be the issue. I can't see how the engine would continue to rev up if all air sources are cut off.

I'm just gonna attach some logs and the map. I really cant seem to figure it out. Even with a tiny tiny throttle blip the RPM just keeps climbing.

Perhaps you have a manifold leak (missing/cracked hose, broken vacuum actuator, failed gasket). Do you have any indication it's in the idle state?

I will try to take a look at the logs, but it may be a few days.

Yeah I'm almost confident its a manifold leak somewhere. I took off the intercooler pipes and even pushed the TB closed by hand and it still wouldnt drop below 1400rpm. Will be removing and checking the gasket to the head from the manifold. Will update tomorrow.

Issue fixed! There was in fact a large leak between the head and manifold! Thanks David!