SkyEyes Posted May 19, 2023 Report Share Posted May 19, 2023 I'll preface this entire post with the fact that I'm trying to learn, and don't know all that much about tuning. I'm having a perplexing issue happen where the car will idle fine shortly after starting and reaching normal temp, but after driving for about 20 minutes, my AFR at idle will become richer and as a result my idle will be higher. This is still my "initial" tune, so I have lambda adjustment turned off, as I'm trying to get my fuel table straight before letting the software correct it. There is also a period of rough idle for about 30-45 seconds after start that's presented the last two times I've started the car (with no change to tune or hardware). Trying to fit time in to keep driving the car and playing around with the tune but my job keeps eating my time and I'm getting frustrated and confused. Any help would be great! My data log file and my tune can be found here at the link below. I should have more time to drive the car this coming weekend to try and get mor data. https://www.dropbox.com/sh/b1foezp12c3894m/AABzNyT-q4VH-TBGxsGMH5l1a?dl=0 Quote Link to comment Share on other sites More sharing options...
Adamw Posted May 19, 2023 Report Share Posted May 19, 2023 Are you sure the IAT is reading correctly? It starts off at 19°C which is the same as the coolant temp before it is started, but then as the engine warms up, your coolant increases to about 95°C which is normal, but your IAT drops to 7°C? It seems a bit unbelievable if to have IAT at 7°C when the engine bay would be 80+, unless it has an ice box charge cooler or similar? Once you confirm that, the other settings you should change is turn off the IAT correction table and put some realistic values in the charge temp approximation table - the example table in the help file is a good starting point for most. Quote Link to comment Share on other sites More sharing options...
SkyEyes Posted May 20, 2023 Author Report Share Posted May 20, 2023 22 hours ago, Adamw said: Are you sure the IAT is reading correctly? It starts off at 19°C which is the same as the coolant temp before it is started, but then as the engine warms up, your coolant increases to about 95°C which is normal, but your IAT drops to 7°C? It seems a bit unbelievable if to have IAT at 7°C when the engine bay would be 80+, unless it has an ice box charge cooler or similar? Once you confirm that, the other settings you should change is turn off the IAT correction table and put some realistic values in the charge temp approximation table - the example table in the help file is a good starting point for most. I wasn't able to drive the car this morning, but I was able to start it and play with settings before I had to go to work. I disabled IAT correction and set up the charge temp approximation table. I did do a preliminary temperature comparison using an IR temperature gun and the temp reading was within 5C of what I was reading on the intercooler pipe. My plan is to remove the sensor and measure resistance as I heat it up somehow. It's a standard GM NTC IAT sensor. This is where I have my IAT sensor. Is this a less than ideal location? I can move it, but if I put it in the intake, I'd have a problem finding a sensor that would reach deep enough to actually sit in the airflow. Quote Link to comment Share on other sites More sharing options...
Adamw Posted May 20, 2023 Report Share Posted May 20, 2023 32 minutes ago, SkyEyes said: It's a standard GM NTC IAT sensor. It is set to bosch in your map. It should be set to Delphi AC IAT. Quote Link to comment Share on other sites More sharing options...
SkyEyes Posted May 20, 2023 Author Report Share Posted May 20, 2023 4 minutes ago, Adamw said: It is set to bosch in your map. It should be set to Delphi AC IAT. I'll make the change and see how the car performs. Thanks! Quote Link to comment Share on other sites More sharing options...
SkyEyes Posted May 23, 2023 Author Report Share Posted May 23, 2023 On 5/20/2023 at 4:13 AM, Adamw said: It is set to bosch in your map. It should be set to Delphi AC IAT. Those changes seem to have made the car run significantly better! Now to fine tune part throttle and figure out why it surges, thank you! Quote Link to comment Share on other sites More sharing options...
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