jmb952

Hello
After troubleshooting why my idle was hunting, I discovered that my closed loop idle target RPM is reading 0. I have an MS2E from Reverant on my 2000 turbo and have been running the same tune for over a year without any issues. Idle has always been solid. After checking my previous log files (when I idle was fine), target RPM was reading fine.
I'm reading CLT values just fine and when I pull up target RPM curve table while idling, I see the tracer hovering over the correct CLT/RPM cells.
Any help would be greatly appreciated.

stefanst

iTrader: (1)

Please post tune and log.

jmb952

Here's my tune and latest log. I began logging right after engine start-up. Idle starts off ok but as you can see, it starts hunting after engine warms up slightly.
I guess I should also mention that my AFRs are a bit on the lean side since this problem began even when it's not idling.
Thanks again for any help.

jmb952

Anyone??
Brian from efianalytics says this value comes directly from ECU in Tunerstudio. Does anyone know what other sensors/variables can affect or drive this value to zero?
Would really appreciate any help. Thanks.

aidandj

iTrader: (5)

I bet closed loop idle isn't activating. So the target is always 0.

If you turn on port status in project settings you can see more data about whether or not its activating.

There is also an indicator on the main gauge screen.

Frenchmanremy

On reverent's MS2E maps, the PID activation lockout is set to on. You can find it in closed-loop settings, right bottom side of the menu.
Meaning that unless your clutch is in, closed-loop won't activate.
I turned that off, CL IDLE turns green now once all parameters are correct for 3 seconds.

jmb952

That fixed it! Thanks guys! Idle is definitely behaving better.
I must have had my clutch in when I was going through my old log files. I still have a small issue with idle hunting slightly to track down but I now know that it's not closed loop idle not working.

jmb952

So I spoke too soon about the idle issue behaving better. It began hunting badly again but the good news is that I believe I finally found the problem. I captured a "Lost Sync Count" in my last log which pointed to the CAS. I swapped it out with a spare I had and the idle has been solid ever since. Up until this last log, the sync count had not been triggered. I guess the CAS finally failed badly enough to set it.