tuckermon

iTrader: (5)

Hi guys,
I've been having this issue randomly, but more often then I think I should.

If I start the car 5-10 minutes after driving for a while (like getting gas, or stopping at a local store), I get high rev idle that goes up and down between 2300 -1800 RPM and just keeps doing that until I turn the car back off and restart. Sometimes have to restart 2-3 times before it corrects.

Attached is a datalog of the issue.

Anyone have any ideas?

soviet

iTrader: (10)

your oscillation seems to be caused by acceleration enrichments. it looks like you are using mapdot instead of tpsdot for enrichment.

tuckermon

iTrader: (5)

Here are my settings.

Braineack

iTrader: (62)

use the accel pump, but those settings dont like that would cause oscillation...I'd have to look at the log later.

Reverant

iTrader: (10)

Sounds like you have high cranking PWM duty, which gets you high enough RPMs to get stuck in overrun fuel cut - no cut - cut - no cut. Reduce your cranking PWM duty values when warm.

tuckermon

iTrader: (5)

Thank you, That makes sense. I see the fuel cut light in tunerstudio when this is happening.

Before and after attached. Look correct? I'll test it this weekend and check back.

Braineack

iTrader: (62)

what idle duty do you normally idle at after the car is warmed up?

tuckermon

iTrader: (5)

I'm using closed loop idle, "Idle Open Duty(%) = 80"

Braineack

iTrader: (62)

that's not what I asked. That's the maximum duty cycle that closed loop will be able to drive the valve. What I want to know is what duty cycle does the MS typically demand from the idle valve to maintain your target idle speed once the car is warmed. hint: you have to log it or look at the idle pwn% gauge.

tuckermon

iTrader: (5)

Rev,
Which did you want me to change:

Cranking Pulse

OR

PWM idle cranking duty

tuckermon

iTrader: (5)

I have a log available to view. What "value/code" do I need to select form the graph choices to get you the info you are asking about?

PWM Idle duty?
Duty Cycle1?

Reverant

iTrader: (10)

Reduce the PWM idle cranking duty.

tuckermon

iTrader: (5)

This has helped a tremendous amount. Now just to fix the cold start timing issues.