MSM_OBrien

Hello!

I have been trying to tune this thing after installing some new bits on it (Skunk2 Throttle body and lightweight flywheel) and cant seem to get this idle dialed in. I can get the car started with a tiny bit of throttle input and it idles ok once warmed up. But whenever I tip in or blip the throttle it dies, sometimes it dies when coming down the RPMS at a stoplight to, I have attached data logs and my tune to see If anyone can give me some pointers. I watched the tuning idle videos by the Pedxing which are very well done and informative but it just isn't clicking how to read data logs and understand where to start. Any pointers would be greatly appreciated and now for my car! (Datalogs and tune are attached).

I have attached some photos of my MSM below just so yall can see the setup.
It is a 04 MSM, I am running 550CC injectors, FM intake kit, "Custom" (Shitty let me practice my welding skills piece) downpipe mated to the stock mid pipe and resonater, MS3 PNP Pro, Skunk 2 Throttle body, 7 lb flywheel and clutch for a 1.6 car, 5 speed trans from my old 97 M edition. I am at 210 WHP and 200 TQ (clutch is good to 270 so I will be able to max out the stock turbo without needing a new clutch for sure).



Stock Interior with a shift handle from my 97 M Edition, AEM wideband mounted on A Pillar

Engine Bay Rats nest, need to trim wiring harness to get rid of all the extra junk I dont have anymore

Crossflow radiator with stock fan, need to seal fan against radiator still.

That valve cover >

Tiny IHI (My drip tray is off while i test and tune things to help expose any leaks)

curly

iTrader: (25)

You're currently adding 26-40% fuel when you blip the throttle, depending on how fast you blip it. You also have no columns that correspond to your idle target in your ignition, fuel, afr, initial duty, or idle VE tables.

I would start by disabling idle VE and zeroing out your AE values. Make all the columns in the tables I mentioned 950 (hot idle target) 750 (a bit below target) and 1150 (a bit above target). Set target to all these values, and tune them individually. Slowly add in AE until it responds reasonably to throttle input. After that, if it still dips when you let off, you could try adding some dashpot.

MSM_OBrien

Thank you so much for responding! I am kinda a visual person so I have attached pictures to help me understand. But what i'm getting is on all my tables I should have more specific rpm values and tune these blocks individually to give the ecu more fine data on what I want it to do for idle. AE needs adjustment and that is fairly straight forward. I am unfamiliar with dashpot so i will do some research on that and get to work.

Thank you!

Zero this out for starting because its adding wayyy to much fuel for what im doing.

add columns in here in addition to the ones already in for low idle (at 750) warm idle (at 950) and cold idle (at 1150) specifically.

curly

iTrader: (25)

Yeah, on that first pic, you're going to press the icon with the three little dots, select the entire upper row, and set to zero.

On all the tables I mentioned, press the button in the button left corner that looks like an up and right arrow. Make the changes you wanna make to the columns, the press apply.

then you'll set your hot target to 750, 950, and 1150, and tune them. Make sure to also turn off idle VE. There's a lot of other tuning issues, but I would start there.

MSM_OBrien

Alrighty, I am working that right now in the house, once i get the tables all set up ill load it up in the car and see what i can do, Thank you for the pointers, I knew i was getting way to much gas but couldn't figure out where to start, with the VE table, idle VE table and AE didn't even occur to me. as I am learning I have discovered there are loads of little places that fuel is added in percentages related to the base VE table, especially when it comes to startup and idle.

Jamikins

iTrader: (1)

Not related to your problem, but you might consider re-binning each table to a usable KPA in order to gain some resolution.

Ignore my VE values (these are specific to my car),each of my fuel/spark/AFR tables are as follows (I run up to 13 PSI, and my idle is at 900:

MSM_OBrien

Good Idea, my little IHI could never pump out 43 PSI to actually use the top of that map, I could decompress the middle section by chopping it off up top.
Thank you.

Jamikins

iTrader: (1)

I had similar issues where I was never returning to idle, so I changed my slow idle threshold in engine states to -1500. it looks like you are having the same issue.

Couple of other things,comparing to my tune:

- Are you using MAP? I noted that your input was not the baro sensor.
- EGO - you are using simple PID, I could not ever get that to run right. I also would suggest using the authority table, but more importantly, you should be using the ego delay table instead of ignition events, and take advantage of the negative authority table to zero out EGO when lifting in certain RPMs/KPA's. Ego can mask idle issues when tuned wrong, or add them when idle is tuned right. Consider tuning idle without this on, but make sure you are keeping an eye on AFR's
- Injector timing - mine are all at 360 (I've never messed with this setting). Not sure if this is adding to the problem
- Similar to your EGO setting, your idle is using simple mode, use advanced mode as simple really doesn't work. I disable CLI when setting my air bypass valve. I like my idle PWM to be at 20% with no load (lights, ac, etc). Have you set up your idle min/max settings properly? My lower is at 12.9.
- Your idle RPM correction curve is super aggressive. I turn off this setting when tuning idle. Mine is set to start at 160 degrees, yours is at 90. The aggressive settings could be adding to your issue.
- As mentioned, your accel enrichment is aggressive, here is mine (still messing with this):



- Unrelated, but your overboost cut is high (if you are on a stock bottom end).

I'm kinda curious why the Skunk throttle body? IMO its really not needed for your level of build, and is likely causing more harm than good as it relates to tuning. It does have a nice bling to it though.

Good luck!

MSM_OBrien

I am using the built in MAP sensor on the MS3 PNP, you guys are bringing up a lot of points that never occurred to me to even consider, such as the EGO messing with my values that I am trying to tune as I am tuning. I clearly have a lot more to learn about this tuning stuff.
I see you have many more points for AE, my table has only 4 entries, are you us MAP or TPS based AE, or a mix of both? Mine is set to TPS based.
The Bottom end is stock.
I got the throttle body after reading multiple posts of peoples engines eating stock throttle body screws and decided that $200 was a very cheap insurance policy, I haven't even port matched my Manifold to the TB yet to really get any benefit from it anyways.
I am done messing with the car for tonight as my exhaust is pretty loud and I don't want to upset the neighbors into the evening but I will try again tomorrow, I started today with a poorly running car and now have an even worse running car haha, but I am moving in a better and more methodical method thanks to yalls help, I really really appreciate it and am doing my best to learn as much as possible.

MSM_OBrien

After reading through all of yall suggestions and doing some more learning ive pretty much decided to re do my idle and everything from scratch, It seemed like the easiest option instead of trying to mess with odd things as they come up. I set up a bunch of the things yall suggested and am working on it right now.

Jamikins

iTrader: (1)

DIY Autotune has some great base maps. I purchased my ms3 from them, with their base map loaded. Car started immediately and idled pretty well stock. They have some maps available for download here: MegaSquirtPNP by DIYAutoTune.com

MSM_OBrien

I had a base map when i bought the MS PNP from DIY Auto tune, but with my skunk 2 TB and a bunch of the other mods im not really sure that's the best option, maybe i will download just to compare some settings and such. I have had the car tuned professionally and it was running pretty good before i slapped on the TB and the mega lightweight clutch setup. I want to learn the tuning stuff anyways for my knowledge to become a better car person anyways so its all an educational experience for me.

MSM_OBrien

I have set up my tables and gotten the car running again. I am getting a loud pop on startup and it runs super rich for a second, I have more adjustments to make on my ASE and WE tables for sure. The car idles higher than target for a while before settling and the hunting is pretty bad after i give it a rev, which leads to stalling. I set up PID controll for both EGO and idle control. my question is should I only have one enabled at a time when trying to tune the values to stop the hunting? my understanding was that EGO was more for corrections while driving above certain RPMs, but now that I set it to PID from Simple the active above RPMs block is greyed out. Also how do the authority table and PID values for EGO interact? my understanding is the authority table "allows" the EGO algorithm to make up ____ % corrections as defined in the table, and the PID values dictate how those corrections are implemented. Is this the correct understanding? I will be searching through the forum more on those questions they just popped in my head as im letting the car cool off for cold start again. Tune is attached with data logs showing the hunting.