Now with larger injectors: I'm giving up bad idle for lent. Help me, brothers.
 

Ha. No religious overtones, just sarcasm.

My 94 is squirted with a Brain built MS3.
The engine is otherwise stock except for a header back exhaust system.
Preparing for turbo, I'm ready to go to larger injectors. I want to get my lumpy idle fixed before switch out and rescale for the new injectors, so as to remove as many areas of potential trouble that I can. Plus it idles like shit and its annoying.

On cold start, the car will idle around 900-1000. After a few minutes or if you blip the throttle, the rpms rise up to about 1600, then fall below 1000, then kick back up agin. The car runs lean when the rpms fall.

Can anyone shed some light on what I can do to correct this problem?

Bonus:
I decided today would be a good day to tackle the problem. Just my luck, my laptop power supply cable is shot. Laptop will not power on. This is the perfect time to find a power supply with a 12v connection so I don't have to purchase a new battery for the laptop that I commandeered from my fiancé.

I go get a new power supply (with 12v!), power it up, open TS, and the program will not see the car. it is in offline mode. I get informed of an update. I click to install the update, I get a pop up window saying EFI Analytics Update is trying to complete but it is unable to rename new file to TunerStudioMS.jar.

Joy.

So, now, even if you guys can point me in the right direction to get my idle to mellow out, I still may have to figure this update issue that I'm having.

Could you post an MSQ and a data log of the idle issues? This will give us more to go on.

Sure. It'll be my first time posting a log. We'll see how it goes ;)

run as admin.

first attempt

seems to fail when I attempt to attach my data log

ignore this attache text file

is the filesize too large?

Your idle settings look pretty good to me, they are pretty much what's loaded in my personal car.

One thing I'd start out by trying is opening the VE Idle Table, switching PID activation to: use PID, and then bumping up the values. Your normal fuel map looks like you should be aiming closer to the high 40s low 50% mark, where you're in the high 30s low 40s currently. Going too lean will screw up idle.

Remember, to use this table when adjusting idle AFRs. Anytime CL idle is active, it will be fueling from this table. The fact that the fuel is reduced at the 42kPa mark over the 35kPa row suggests it's not tuned well.


I'll need to see your log to suggest other things that may help, like your closed loop idle initial values table.

says its 2.22, site says it can be 2.91 max

maybe I can try trim it down a bit?

I just increased the file size limit.

well, that didn't work either

Manage Attachments
Upload Errors
2013-02-14_09.26.01.msl:
Upload of file failed.

this is the only warning I can see, it doesn't give specifics

I'g going from TunerStudio, to my current tune, to datalogs, to the log file.

rename it so it has only one dot before the msl, i wonder if it's getting confusesededede.

lets try a different one

this is a little piece of log when I was making sure I knew what I was doing

Handy trick, for files you're having trouble uploading. ZIP them.

Assuming you are using Windows, right click on the file, and select "Send To" and then "Compressed (zipped) folder"

https://www.miataturbo.net/attachmen...1&d=1360855050

This will create a new file of the same name with the extension .ZIP, which you should be able to upload.

I renamed it, still nothing. Interesting that I can upload a smaller one with no problems.

sweet, thanks Joe Perez!

14.msl worked.

Idle valve isn't even doing anything. that log shows it stuck at 19.5% throughout, which for all intents and purposes should be considered closed.

14 was basically just startup

14idle was the log that started where 14 ended

Was this from the 14idle compressed log file? Or was this from the 14 log file that was real short?

the first. 14.msl

on the compression file, 14idle.msl, the idle valve doesnt even start to work until record 389.035.

it looks like that's the point where you blipped the throttle and then CL idle finally kicked in. Unsure why that's the case. It's not until that point where the idle code is acutally trying to do anything.

I'm looking at this in excel so it's hard to really get a clear picture until I can see it in MLV.


when you start the car it should open the valve to the values dictated in the PWM idle cranking duty table. then that should decay out to the closed loop inital values table, where. So you're jumping from closed (19.5% PWM) to open initial target (~35% PWM) and I can see why the idle speed would shoot up. Have you ever adjusted your idle speed scre on the TB? your idle should be close to 600-700RPM when the idle valve is showing 19% PWM, not ~1200RPM.

I blipped it to get it to get it to start the idle droop, took the car down the street and back, set for a bit with idle droop,then shut it off.

It usually starts the droop the first time you touch the throttle, which for me is when it gets backed out of the garage.

yeah that's odd, if you look at the PWM IDLE% log you can see what i'm talking about, your valve has a working range of 20%-60%. for some reason, it's not kicking on until you first blip the throttle. I'll have to look at the log in MLV to hopefully figure it out.

Thanks man!

also under Accel Enrich, Accel Enrich Settings, change EAE from X-tau to EAE.

Not sure why you have the X-tau code active...

also change the range to like 2500-5000. I think 1000RPM is a little too soon to start decaying.

I made the changes you listed for me.

It is still there, but I would say it has improved a bit. Here's a log. Looks like it loads smaller file sizes with no problems.s

Today I had time to mess with the car a bit.

The idle started lumpy as always but then it suddenly smoothed out.
I grabbed my laptop and took this log of what has been the smoothest idle since I installed the MS in my car over the summer.

Can anyone tell me if my idle AFR is normal? It seems to bounce a bit but its a lot smoother than the compressed log I posted on page 1

Here is a log from today.

I installed FIC 650 injectors.
My required fuel on stock injectors was 11.9.
Math told me that I should now use required fuel of 4.85 (265/650= .40 x 11.9 = 4.85)

The car started up after its usual first crank stumble.
No leaks.

The drooping idle (reason for this thread) showed up after the first blip of the throttle.

Not sure if changing injectors in the middle of diagnosing my issue would complicate this problem, but I'm still looking for help trying to figure out my lumpy idle.

Can someone look at this newest log and help me out?