Hunting idle - what is conflicting?

[M1tch]

Hi all,

I have recently rebuilt my engine ready for boost, its currently going through break in and running it NA so I can't really idle the engine for long as its only got about 60 miles on it (although close to be broken in at this point - pulls really well).

Anyway, I have always had an idle issue where it would sometimes hunt around, I have used another Link map file off someone else to change the base position tables so see if that's causing the issue - its current set to around 45% when warmed up although have noticed that it sits at around 59% when checking the realtime data.

I am aware that I need to cut some fuel out - its a new engine and its using slightly more fuel due to the slightly different built vs the previous engine but its correcting around 5-8% - I have also made sure that the ignition table 1 and the idle table ignition are closely matched although it looks like I might need to change one of the breakpoints as its idling more around the 40-45KPa mark rather than the low 30s as with the old engine so might need to pull timing from the 50 kpa low load areas which might fix it.

Can someone check through the log and map files attached to see if there is anything else that is the issue or if I there are any setting conflicting at all - my thoughts to fix this at this point would be to:

• Adjust Ignition table 1 to pull timing from the low load, low rpm cells to match closer to the idle table
• Disable the closed loop lambda and look to manually pull fuel out of the idle table
• Increase the Idle base position table slightly higher

The rest of the mapping seems to be pretty good on the road, will need to tidy up the fuelling a bit with the new engine but its running well - just need to sort the idle out.

Thanks in advance!

Edit - just noticed that my ECU is set to closed loop idle - should I look at running open loop?

130820 idle take 2.llg 13082020 reset idle.pclr

[Adamw]

It looks like a bit of a mixture of many factors.  I have made some adjustments to your map, you can use the compare function in the software to see what I changed.  Give it a try.

I richened up the idle target lambda to .96 as many engines arent happy idling at 1.0.  I have flattened out your fuel map around the idle region.  I have made idle ign a bit more agressive and have adjusted the idle base position table - this really needs calibrating properly in open loop mode but it should be closer than it was.

Also, your injection timing looks pretty odd, I didnt change it, but I suggest you try adjusting it while idling to see if it makes it run any smoother, most of the time it makes little difference, but it is more common to be around 380deg, whereas yours has 250deg at idle.

Tweaked idle.pclr

[M1tch]

11 hours ago, Adamw said:

It looks like a bit of a mixture of many factors.  I have made some adjustments to your map, you can use the compare function in the software to see what I changed.  Give it a try.

I richened up the idle target lambda to .96 as many engines arent happy idling at 1.0.  I have flattened out your fuel map around the idle region.  I have made idle ign a bit more agressive and have adjusted the idle base position table - this really needs calibrating properly in open loop mode but it should be closer than it was.

Also, your injection timing looks pretty odd, I didnt change it, but I suggest you try adjusting it while idling to see if it makes it run any smoother, most of the time it makes little difference, but it is more common to be around 380deg, whereas yours has 250deg at idle.

Tweaked idle.pclr 157.64 kB · 2 downloads

Thank you so much for having a look at this, will load it onto the ECU and see what it does - will look into calibrating it properly in open loop.

With regards to the injection timing, I will set it back to stock as per base maps, I think its usually at 400 or so across the board - the table has been tweaked after using data from the HPA remote dyno as they use a 1zz as their test engine although its only really the very very last thing to do for the last few bhp so I will just set it back to how it used to be a while back to avoid this being the issue.

Will report back once I have run it a bit!