Cold start idle surge and surging after quick throttle blip
Two scenarios I'm trying to work out.
1. When I start the engine cold, the idle surges up and down a 150-200 rpm for about 30-60 seconds.
2. sometimes when I blip the throttle while going about 5mph the idle gets into a loop where it won't settle at 800 but continuously dips and overshoots the target until you hold it a bit higher with the pedal for a couple seconds.
2001 LS1 with Torquer v2 cam and TSP heads. 4l60e
Been through the MAF and VE tuning and base airflow tuning a few times. All that seems good.
Assuming BRAF/MAF/VE are all good, where should I look to make adjustments?
I had thought maybe for the throttle blip issue I just need a little more follower or maybe adjust how aggressive the idle rpm error correction is -over/under speed maybe?
And for the cold start either take the easy way out and increase the cold idle speed a tad or look to adjust AFR at the lower temps that its hitting. Or perhaps adjust the base airflow at lower ECT? Right after startup I see the AFR fluctuate between 10.2 and 11.2 during the surging and timing is being added/subtracted quickly.. like its fighting itself too much.
Having the same issues with my heads cam ls1 camaro. The cold start is horrible and its always randomly surging and dying. Wondering if I should change my injectors from racetronix 42lb to some fast injectors. I was told they may have something to do with the surging as they don't have good injector data.... any help?
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