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Fury - What happens during idle?


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Fired the bike up, was good to hear it run again.  Starts okay from cold, goes to a higher then normal idle and then after 6 seconds the revs start to climb from 1800 to 3000 then 6 seconds later it noses over and stalls.

This is a Fury running an internal wideband (which is working) and CLLambda is set at 50C. (so no logged CLLambda adjustments)

I was tempted to lower the CLL ECT lockout so it auto adjusts but I suspect I should be fixing the issue instead of hiding it.

Can someone please make a suggestion of where to start tweaking?



Edited by ayjayef
-- removed the old log and map files --
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Your ignition table is in MGP, and doesnt go into negative. This means your ignition timing at anything non-boosted is effective a single row lookup. I notice it runs pretty minimal vacuum anyway, but you should still have this drop down to at least -30kpa as it seems your engine would use this at idle.

Your fuel table numbers are very small, and your master fuel number is quite large - this doesnt "break" anything as such but it makes it very hard to get any resolution in your fuel table. eg you can only move from 12.0 to 12.1 and this might be quite a jump in injected fuel quantity. Try changing master fuel trim to 0, master fuel to 5, and then select the entire fuel table and type *4 <enter>. this drop your master fuel value to ~1/4 of what it is now, and multiples the table values by 4. The injected quantity will be the same but its easier to work with the fuel table now. 

It looks like the reason it stalls is because it runs too lean. healthy idle is probably 0.9 lambda and 1.1 is probably stall. Post start enrichment is keeping you going to start with, and when it runs out, your engine goes lean and stalls. Try bumping up your master fuel table a little bit (maybe from 5 to 6 once you do the step above) until it can keep running once post start enrich goes to 0. Then once you know what "stable" idle looks like, you can reverse engineer the post start enrichment numbers to stop the idle creeping up at the beginning but this temporary high idle is not your biggest problem right now.


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Hi CJ,

I'll adjust the ignition table, that makes sense.

I had planned on multiplying the fuel table to get a better table resolution, thanks for confirming I should.

Bingo! - Post Start Enrichment was the bit that I didn't understand.  I thought something was adding fuel for a short amount of time but didn't know where to start looking and everywhere I looked wasn't doing anything.  Makes way more sense now I know what I'm looking for.  I had seen (somewhere) a table/image of the startup process but can't find it now.

Thanks heaps for the reply.

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Oh one more thing, are you running E85 in this engine? you've defined the stoich ratio for your fuel as 9.8 but it should be 14.7 for petrol. This wont be hurting anything yet, but might once you start using closed loop systems.


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Yeah, it's E85 (prob should have mentioned that).

The high number in the master fuel was just me adding a pile of fuel to a petrol base map to get a starting point.  Now I understand why the idle was high then leaning out it will be easier to make adjustments and add things like the enrichment to the log to see what's going on.  Great tips! 

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