Miata Turbo Forum - Boost cars, acquire cats.

Miata Turbo Forum - Boost cars, acquire cats. (https://www.miataturbo.net/)
-   MEGAsquirt (https://www.miataturbo.net/megasquirt-18/)
-   -   Rev. built MS3 suddenly won't idle, log included (https://www.miataturbo.net/megasquirt-18/rev-built-ms3-suddenly-wont-idle-log-included-76314/)

6speed 11-29-2013 06:08 PM

Rev. built MS3 suddenly won't idle, log included
 
2 Attachment(s)
I had the laptop hooked up, so I got a couple of logs. This isn't the 1st time it's happened, but every other time it quit before I could log. Every time I pushed in the clutch or let the rpms drop to less than @2300, the motor would begin cycling up and down from 2000 to 2500 rpms.

Ben 12-02-2013 12:08 PM

The high idle surge appears to be caused by a lean spike. Can you post a copy of the tune that was installed in your ECU at the same time the log was captured?

6speed 12-02-2013 12:34 PM

2 Attachment(s)
Current tune attached

Ben 12-02-2013 01:24 PM

That's the tune that you're running? What exactly are you doing with the table switching? Your VE3 table makes no sense.

Idle is being upset by your over run fuel cutoff. Your motor idles at a MAP that is below your trigger setting. Disable over run or set it to engage at a lower MAP.

6speed 12-02-2013 05:18 PM

I didn't realize I had table switching enabled or that I was even using the VE3 table. I switched that off, thank you for the insight. Somewhere a town is missing it's idiot, and I don't know how to get home.

I'm going to disable the fuel-cut and see if that helps things.

6speed 12-03-2013 07:50 PM

Had a few minutes to mess with the car. I disabled over-run and the rpms wouldn't drop below 2500. I pulled the Idle valve off the car to look for any leaks around the gasket or any obstructions inside, and everything looked fine. I had recently enabled the "initial map reading" for baro correction and I "included AFRtarget" in load parameters. I wouldn't think either one of those would cause this problem? Any other insights into the tune I'm running?

DNMakinson 12-04-2013 10:18 PM

Your iac duty cycle is way too high. This makes me think this: Mine did that when I was using the "use last value" for pre-setting the iac duty cycle. I fixed it by going to "Use initial value table" and then filling in the table with real values. That was for closed loop, but you may be using open loop, in which case 68 duty cycle seems very high to me, and could also be part of the problem.

I think I just repeated myself, but I'm leaving it.


All times are GMT -4. The time now is 05:39 PM.


© 2024 MH Sub I, LLC dba Internet Brands