Ibasaka Posted January 19 Report Share Posted January 19 Hi All, I have a Toyota 3 wire ISC valve (OEM 4AG 20V) wired into aux 1/2 on a MonsoonX. It is wired in the following manner: AUX 1 -> RSC (Rotary SW Close) B+ -> 12V AUX 2 -> RSO (Rotary SW Open) The issue I am encountering is that the rpm begins to rise to 1500 from 950ish and idle hunt as the car warms up. I am able to mitigate the hunting and bring the car back to a steady 950-1k idle by going into the idle speed control settings and activating "Test Aux 1" which I am assuming closes the ISC valve. Please advise. Base map is attached below. 4age 20v 1-17-23.pclx Quote Link to comment Share on other sites More sharing options...
Adamw Posted January 19 Report Share Posted January 19 Sounds possibly like the valve is working in the wrong direction. In the idle control setup, try changing the Aux 1 active state to high, this will reverse the logic. If that doesnt help then please do a short PC log. Quote Link to comment Share on other sites More sharing options...
Ibasaka Posted January 19 Author Report Share Posted January 19 Thanks Adam, I'll give that a try. One more issue I am encountering is that it appears that there is a 2800 rpm rev limit on the tune above. I cannot find the option that shows it is enabled. I want to verify that it is in fact a safety feature turned on and not a mechanical ignition issue. Thanks again. Can post a log if needed. Quote Link to comment Share on other sites More sharing options...
koracing Posted January 19 Report Share Posted January 19 If you can take a PC log of this happening and post it up it would be helpful to find any limiters set up. I can confirm using a Toyota 3 wire ISC valve pinned to the outputs as you have does require active state to be high. Also record a log while warming up for the ISC values. Quote Link to comment Share on other sites More sharing options...
Ibasaka Posted January 19 Author Report Share Posted January 19 Here is a log of the ignition cutting, Ignition Cut Log.llgx EDIT: Ah... 24 trigger errors.... Quote Link to comment Share on other sites More sharing options...
essb00 Posted January 19 Report Share Posted January 19 ECU turns off fuel & ignition whenever it loses the engine position due to unstable/unreliable trigger signals. Could you again take trigger scopes, perhaps on idle and another around 2krpm? Quote Link to comment Share on other sites More sharing options...
Ibasaka Posted January 19 Author Report Share Posted January 19 Here are the trigger scopes for the rpms requested. Log as well Thank you for the support! 1k and 2k rpm log.llgx 1k and 2k rpm trigger.llgx actually I hope these are a bit more useful.. 1k rpm scope.llgx 2.5k rpm scope.llgx 2k rpm scope.llgx near cut scope.llgx Quote Link to comment Share on other sites More sharing options...
essb00 Posted January 19 Report Share Posted January 19 Yeah... there, for some reason your Trig 1 voltage is lower than other 4A-GE stock triggers I have encountered -- where your Trig 1 voltage peaks touch below the arming threshold. Adjusting the trigger arming threshold (as per attached below) should remedy that, but try to adjust the gap/clearance of the NE pickup to the teeth. If I remember correctly minimum clearance as per repair manual should be 0.4mm. Quote Link to comment Share on other sites More sharing options...
Ibasaka Posted January 19 Author Report Share Posted January 19 I took a look at the distributor a few days ago and encountered this. Pickups were fairly corroded. Cleaned up with fine Emory cloth and car fired up. It appears to be non adjustable though :/. Updating the arming threshold fixed the cutting issue. Will be locating another distributor to compare voltages. Thank you for your support! Quote Link to comment Share on other sites More sharing options...
essb00 Posted January 20 Report Share Posted January 20 Although your Trig 1 voltages seem low, they appear to be clean in all the scopes you have attached - so it will be fine. ...but yeah, it would be nice to have another dizzy just to compare and to have it as spare. Quote Link to comment Share on other sites More sharing options...
Ibasaka Posted January 20 Author Report Share Posted January 20 Got the car tuned last night and made decent power for a 1.6 4ag Ended up reducing the threshold a bit further up top and did not encounter any misfiring. Switching the ISC active state to high did in fact fix my idle issue as well. Thank you Adam, Koracing, and Essb00 for your support! Hafeez Zudin, koracing and essb00 3 Quote Link to comment Share on other sites More sharing options...
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