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I am trying to sort out some rough idle, or actually just operation, with lower water temperature <65degC.
I have been lurking the forums and gone through my map, and thought the issue was the "IGN vs WaterT Cool" which was 15. I changed this to 0 as suggested in various threads in here, but it is still kinda rough.
As soon as the waterT hits 65degC idle smooths out and has steady AFR at approx. 12,6. below it stumbles and AFR hunts between 12,6-13,2 ish.
Am i missing something in the map?
I tried changing the Water temp correction table, but it seems like more af an ignition issue.
Car is single turbo, street port, 850cc injectors primary and secondary, twin power, all emission controls deleted, ICV deleted, Thermowax deleted.
Engine was rebuilt perhaps 5000km ago, and i am almost certain this is an issue with the map or a setting as it always smoothens out at and above 65degC.
Your support is highly appreciated!
I attached the map for reference.
The default power fc ignition settings won't cause what you are describing. The fuel settings absolutely will though. It being temperature dependant like that would suggest it's a correction map that needs adjusting. You said you already tried with the water temp correction but try again. Make a MASSIVE change to increase fuel. 50, 60, 70% if necessary in the applicable temp sections. Just keep adding fuel until it smooths out because there's a good chance it will.
Try this and report back. Although it seems like it is entirely a map setting, there is a chance it's not but let's rule out that possibility before considering a mechanical fault of some kind.
Post a picture of your sensor check screen with key on and when running on a cold start
if you're using the commander, there is a screen that changes things until you turn off the key, so its easy to try different fuel and timing, and then you can go in and change the map later
in the setting menu its the IGL/T, FI screen.
The default power fc ignition settings won't cause what you are describing. The fuel settings absolutely will though. It being temperature dependant like that would suggest it's a correction map that needs adjusting. You said you already tried with the water temp correction but try again. Make a MASSIVE change to increase fuel. 50, 60, 70% if necessary in the applicable temp sections. Just keep adding fuel until it smooths out because there's a good chance it will.
Try this and report back. Although it seems like it is entirely a map setting, there is a chance it's not but let's rule out that possibility before considering a mechanical fault of some kind.
Post a picture of your sensor check screen with key on and when running on a cold start
I already tried adjusting the water temp correction table quite extensively with no results. i will try again and feedback.
However, as the table increments are -30, -10, +10, +30, +50, +80 i am not sure they are linked. It is not like the idle smoothens gradually but more like night/day when reaching 65degC.
Perhaps some flaws in the map, but still think it is strange as it seems to be VERY temperature dependent.
if you're using the commander, there is a screen that changes things until you turn off the key, so its easy to try different fuel and timing, and then you can go in and change the map later
in the setting menu its the IGL/T, FI screen.
I am not a native english speaker, so i am not sure i understand.
In any case the issue seems very temperature dependent and i am not sure ignition map is the fault, as there are no issues above 65degC watertemp.
Also, i do not feel confident fiddling with the ignition-maps
Did some more reading and testing and it appears the idle timing will be locked at -5 IGL and 15deg split with idle control off and water above 60degC.
I adjusted the map to have -3 deg IGL and 0 split in the idle cells and it improved cold idle significantly!
Now the AFR's are crazy rich but i will try to adjust TPS before touching the fuel maps.
As you noticed the split timing on the cold idling cells was too high, which resulted in low compression and poor idling. The map is in an overall very bad shape, meaning that you could easily damage your engine if you do not tune it properly. I suggest getting FC-Tweak tuning software which will automate the whole tuning process. I did a quick scan on your file and you've got over 400 bad/ unoptimized settings that need to be corrected.
As you noticed the split timing on the cold idling cells was too high, which resulted in low compression and poor idling. The map is in an overall very bad shape, meaning that you could easily damage your engine if you do not tune it properly. I suggest getting FC-Tweak tuning software which will automate the whole tuning process. I did a quick scan on your file and you've got over 400 bad/ unoptimized settings that need to be corrected.
Regards
Xavier
Unfortunately, I cannot say that I am surprised. I have not done the tune (it was done by PO) and rotary experts are very rare, if not non-existing, where I am from.
However, the car has been running with this map since 2017 without blowing the engine.
Is it the best or most efficient map, no! But it works and I may be going Haltech this season hence i wont put too many efforts (or money) into the PFC.
I will try tweaking the ignition tables to find a sweet spot for my idle.
