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ignition angle dropping out


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as titled im having a problem that when the engine warms up it starts hunting at idle and ive checked the log and the ignition table will be reading 18 and the ignition angle will be reading the same then the ignition angle will drop to zero for a second then return following the ignition map then drop again.

i thought it could have been trigger related but im getting no trigger errors or any other errors .

has anyone got any pointers where i should start looking thanks.

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forgot to add the log here is one not the most current but same problem and a copy of the map again dont think its the current one but im on a diffrent laptop

 

ive even looked back on my old vipec setup and it was doing the same on that

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Your cam sensor is wired back to front, Im not sure if this is the cause of the problem but thats the first thing to fix - swap the +/- wires on the cam sensor.

 

9 hours ago, max said:

its even doing it without the engine on

That is normal - dont ask me why but its always done that since way back.  Not related to what you are seeing here.  

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ive got longer logs but it wouldnt let me post

 

also the lambda not tracking the afr target is part of the problem.  say its target idle is 980 i will set say a 4 square block were it will idle and set the number to achieve my desired afr.

so say i put 20 in them 4 boxes to give the desired 14.7 but because it hasn't got a smooth idle. it then wants to drop in to the 750rpm box were that number to get the afrs right is in the 30s so its just wildly swinging the afrs so im having to alter other boxes just to get it running somewhat smooth

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Ok, it looks to me like we have solved the ign dropping to zero problem now, is that correct?  Do your longer logs show the ign dropping to zero like it did before?  BTW, if you want to attach more files then share it using google drive, onedrive, icloud drive etc.

As for the idle hunting, there are a few things all contributing.  Mostly though it is the throttle causing it.  I would start by increasing the ISC deadband, something like 50RPM is more common for DBW.

DBW idle control is too slow to give good idle control on its own - by the time it opens to increase idle RPM, there is already enough air in there for it to overshoot - then it has to close again and so on.  So you need ign control to work in conjunction with it.

For idle ign control to work well you are going to want smaller numbers in the idle area of your main ign table - usually around 10deg gives you enough authority for the idle ign to quickly increase torque when it needs to.  

So if you have 10deg in the main ign table, then you want your idle ign table to look something like this:

gj8uWFp.png

You may have to play with the numbers either side of the zero cell if this is too aggressive.

The fuel table needs to be flattened out around idle area too, switch to graphic mode and you will see what I mean.

 

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hello thanks for the help yes ign dropping has no been resolved by turning idle ignition control off. so it must be an incorrect setting in there somewhere.

theses were the setting i was using do these look ok 

2020-02-08.png

i will change the other settings as suggested and report back tomorrow

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2 hours ago, max said:

hello thanks for the help yes ign dropping has no been resolved by turning idle ignition control off. so it must be an incorrect setting in there somewhere.

In your earlier logs with the ign timing going to zero, the idle ignition was rarely active and the table didn't even have any zeros in it so the "dropping to zero" was not resolved by turning it off.  The dropping to zero was caused by the ecu losing sync every few revolutions due to the cam wiring.  That's not to say however after fixing the cam wiring that you then had an idle oscillation that was related to idle ignition control.

 

Based on your log, I would change the idle ign activation conditions just a little, try something like:

MAP lockout 45kpa.  RPM lockout 1300.  AP lockout 0.5%.

 

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ok i will try it but when i changed the cam wire round the correct way it had no effect on the original problem it was still dropping to zero every few seconds it only stopped dropping out when i disabled idle ignition control.

from cold it run fine untill it hit 26c then it started doing it so at a guess it appears its something that turning on based on temp.

here is the log of when i first rewired the cam the correct way and ignition idle control still active.

 

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done all the above and its now much better when warm it still dances around when warming up but when warm its a stable idle  ive block changed the fuelling when it was warm so will wait till it cools and take a log of it starting and warming up from cold and report back

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