XFI...cold start...idle is up/down

[MSDGN]

On a cold start I have 2 issues...1) usually have to crank for awhile before it starts...2) after it starts the idle goes up/down like it's running real lean...only lasts about 30 seconds or so then the idle smooths out and it's OK...warm/hot starts are fine...what can I tweak to correct these issues?

 

[Fuelie Nova]

My guess would be cranking fuel vs. coolant temp on the first problem and possibly afterstart enrichment on the second problem. Still a newbie at XFI, will be curious what others have to say.
Tg

 

[Dusty Bradford]

If giving the car some throttle helps the initial start, raise your cranking IAC value.

You still may need some work on your cranking fuel vs coolant temp. Add some and see if it helps....go the other way if it doesn't.

After it starts, you need to make sure your idle rpm vs coolant temp is correct. Then afterstart enrichment like Fuelie Nova already mentioned. Then the VE table to make final adjustments. Your target afr should also be in the 12.8 range. You can play with this after you get it sorted out to find where the car likes to idle.

 

[1BADTT]

Your target afr should also be in the 12.8 range. You can play with this after you get it sorted out to find where the car likes to idle.

Dusty, is this A/F ratio your stating @ idle ?

 

[Dusty Bradford]

Dusty, is this A/F ratio your stating @ idle ?

yes. I run afr target at idle anywhere from 12.5 to 13.5 depending on what the car likes.

I'll usually turn closed loop off and tune the VE table to get the car to idle like I prefer. I'll then take the afr the car idles best at and put that into the target afr and turn closed loop back on.

Also I have found most cars like 36-38 degrees in the lowest 3-4 lines on the timing map. This keeps the plugs clean and helps idle.

 

[1BADTT]

Thanks a lot !!!!

yes. I run afr target at idle anywhere from 12.5 to 13.5 depending on what the car likes.

I'll usually turn closed loop off and tune the VE table to get the car to idle like I prefer. I'll then take the afr the car idles best at and put that into the target afr and turn closed loop back on.

Also I have found most cars like 36-38 degrees in the lowest 3-4 lines on the timing map. This keeps the plugs clean and helps idle.

Great 411 ! Thanx !