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Erratic Idle bounce up and down


Dualxeon64

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I have a linkecu g+4 st185 on a 1991 toyota mr2. I have been trying for over a week now to sort this issue. I have tested my injectors to make sure they are working. I have checked and confirmed stable spark, checked wiring to injectors all seems to be right. I have even tried using only one pump then the other pump to see if its a fuel pump issue. So this is either an issue with an ecu setting or maybe my injectors are not being consistent. Any help to figuring this out would be awesome. I am including my current tune which is not complete because im stuck at the idle issue. I am including a trigger capture it wont let me attach the log says it exceeds file size.

trigger.jpg

newmap.pclr

Here is the log file

log1.7z

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7 hours ago, Adamw said:

Your MAP sensor isnt working in that log, so that would be the first thing to fix.  The lambda sensor isnt working either but that is not going to influence idle - just will make tuning difficult.

Here is a picture of the injector information and I included the log as well.

20201003_100924.jpg

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47 minutes ago, Adamw said:

So what is the actual problem?  You said the idle bounces up/down but it is a flat line in this log +/-50RPM.

Yes it will be plus or minus 50 then it will drop 100 or 200 then come back up and go up plus 100 or 200. Cannot get it to be consistent. At this point there is no sensor or wire I have not replaced or tested. I can run a longer log if that helps. My tuner says with the current idle it is untenable.

54 minutes ago, Adamw said:

So what is the actual problem?  You said the idle bounces up/down but it is a flat line in this log +/-50RPM.

Here is longer log file, I can clearly hear the idle be consistent then jump and come back or drop and come back.

Log 2020-10-3 4;19;24 pm.llg

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Your lambda is pegged at max rich 0.68 Lambda, so that would be its even richer than displayed - it is not going to idle well like that.  What happens if you lean it out to something more normal?  Also your manifold vacuum is only 68kpa, does it have big cams or is the cam timing out or something?  

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6 hours ago, Adamw said:

Your lambda is pegged at max rich 0.68 Lambda, so that would be its even richer than displayed - it is not going to idle well like that.  What happens if you lean it out to something more normal?  Also your manifold vacuum is only 68kpa, does it have big cams or is the cam timing out or something?  

Yes it has big cams. Brian crowder 272s.

 

When I try to lean it out it still stays pegged even tried adjusting fuel pressure. Only changes if I raise the rpm above 2k the it leans out. This leads me to possible injector issues.

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Are you on ethanol or petrol?  

I suspect a smooth idle at 900RPM with 272 cams and 2200cc injectors might be asking a bit much if running petrol.  Ethanol might get there.  

But Im a bit suspicious of either your wideband or Injectors too.  

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2 hours ago, Adamw said:

Are you on ethanol or petrol?  

I suspect a smooth idle at 900RPM with 272 cams and 2200cc injectors might be asking a bit much if running petrol.  Ethanol might get there.  

But Im a bit suspicious of either your wideband or Injectors too.  

I am running e85. I expected some lope maybe bounce 50rpm up or down from the center. So 100 span but the current bounce is far more. I'll take my injectors for flow and leak test and see what the results are.

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