Idle Tuning: Here's What You Need To Know 

Glad you like them, cheers Mike! - Taz.

indeed.

Happy to help!

It's one of those things, once you DON'T have it, you realise how great and important it is! 😅 - Taz.

Chur! Hope you're keeping well and enjoy the next [TECH TOUR] release on Tuesday too. A JGTC 350z 😎 - Taz.

Post start fuel corrections - table for coolant temp vs post start time (seconds) Add more fuel at hotter coolant temps that drops off over time (enough time to keep everything happy until WB turns on has worked for me)

Start with it closed see what the idle control valve does. Use a wide band afr to see what it idles at, then I assume that you would use that little actuation adjustment to fine tune your closed angle to the ecm to get them in sinc, so say throttle closing angle is 1% then back that fine screw till it’s 1% open. Still super rich then open it to 1.5% and continue process till your ecm and throttle plate opening and closing % are in sinc. If it’s drive by wire the ecm and throttle plate need to know where each other are so your requested torque and, load compensation tables are able to work correctly

We do cover cold start, not sure if there is anything on YT off the top of my head but search on the HPA site here and you'll find a few lessons for sure. Remember it doesn't have to be the same ECU you have to give you solid knowledge on the process that still applies to you and your setup - Taz. www.hpacademy.com/previous-webinars/?

timing is crucial at idle, specially cold; try the same original settings with a bit more advance and see the results

This is the full lesson, if it stopped part way though that is a device or connection issue. We also have paid course material over at www.hpqcademy.com covering other topics 😎 - Taz

You can use ignition timing

Probably not. Why not use a bypass valve?

@@sexyfacenation my plans was to make a custom dual plenum with dual tbs. The TB Im going to use doesnt have iac . So Id have to come up with some external solution in that case. The car is a hobbyist car only driven during the summer. But I guess it would be easier to inculde an iac..

@@magnusdanielsson2749 best plan is use dbw. Do that!

Yes, *but...* As in: Yes, but only in a narrow range of situations. Idle tuning your intended setup would be identical to ITB's: with the engine at running temperature, adjust the throttle stop so it's open enough for the engine to idle at the intended speed, then use the ECU's spark scatter control (I think he called it "idle-up") for closed-loop idle control. But, also like ITBs, you'll still have to nurse the engine a bit on cold starts, or other certain situations.

We are still a little way off Holley content, we do have a unit here waiting and it is going to happen but I don't have anything for you right now sorry! Have you checked the Holley forums though? I did a quick search on those terms and it looks like there is some info on it from the community for you which might be good enough rather than needing a course or something 😎 - Taz. forums.holley.com/

@@hpa101 I have not yet, but I will go give that a shot! Thank you.

A common algorithm for control loops is called "PID" control, which is short for "Proportional, Integral, Derivative". When you see terms like "P" and "D", those mean "Proportional" and "Derivative" (the "Integral" term is often unused). Those words have meanings in calculus, though it's not at all necessary to know calculus to tune a PID loop. For PID control, the strength of the correction is always based on the "error", which is the difference between the target value and the measured value (e.g. if your idle speed is 960 RPM and the target is 900 RPM, then the error is -60 RPM). The P term will apply a correction that is proportional to the error: for example, maybe you'd set it up so that it applies an extra 5 degrees of timing advance for every 100 RPM it drops, and -5 degrees for every 100 RPM it's up by. Proportional corrections can be thought of like a spring, since the force from a spring is proportional to the amount it's stretched/compressed. A larger P term means greater "stiffness". The D term will apply a correction based on how fast the error (i.e. the RPM) is changing, so you can set it up to advance timing if the RPM is dropping too quickly, or decrease timing if the RPM is rising too quickly. You can think of D as "damping", because that's exactly what a damper/shock does: it creates a force based on how fast it's being extended/retracted. It's useful for preventing the RPM from overshooting or oscillating around the target RPM. The integral term applies a correction based on the average error over time, which can be useful because the P term alone will never actually bring the error to zero. A light amount of integral control will correct for that lingering bit of error, but too much can actually cause oscillations. Usually, it's best to first set all the PID terms to zero, then tune the P term, then D, then I if needed. You can tune P by turning on accessories like headlights and climate controls to load the engine a little, and add enough P to prevent the idle from "sagging" too much. Then you can start adding in D if needed, though I don't think it's often useful for idle ignition tuning unless it's used as a bandaid for the AFRs leaning out when the RPM is falling.

@@agerrgerra1361 the Holley stuff has a pretty rudimentary idle spark control setup. Just has a box to enable the feature and a P term and D term value. No table per say. The default was 50 on the P term and 40 on the D term.

@@agerrgerra1361 Thanks, that's the clearest explanition I've heard on PID. Better than the accelerator/brake example.

Does it say 'era' in the subtitles? Throw me the timestamp and I'll touch them up, usually we already have them on point. Sorry about that! - Taz.