Cammed ls1 idle surge/idle hanging

[Da71bird]

I have a cammed ls1 with idle surge when coming to a stop after engine is at operating temp. Rpm?s come down slowly to idle then drops below idle set speed to around 500 then jumps to 1300 up and down. Sometimes when coming to a stop idle will come down then bounce up to 2000 and hang. Rpm?s always come down slow. I have no problems driving. This car has been to 2 dyno tuners since it was built in 2020 and out of frustration and money spent the car just sits and gets started a few times a year. The build I the original 98 ls1 with torquer v2 cam, Dorman ls2 intake, Holley 90 tb 243 heads and 60lb injectors. The tps and iac were put in new from the build and were ac Delco. The iac counts right now are at 102 and I cannot bring them down any lower or it will immediately surge. It will sit and idle fine until I driving it around and come to a stop. It is not every time but more times than not. I?m about to swap a stock engine in it as this point because I miss my car. Please help

[SiriusC1024]

Post the tune and log, friend.

[blindsquirrel]

Put down phone, use PC, post files like it says in the sticky thread at the top of the forum that you didn't bother to read.

[Alvin]

I have a cammed ls1 with idle surge when coming to a stop after engine is at operating temp. Rpm?s come down slowly to idle then drops below idle set speed to around 500 then jumps to 1300 up and down. Sometimes when coming to a stop idle will come down then bounce up to 2000 and hang. Rpm?s always come down slow. I have no problems driving. This car has been to 2 dyno tuners since it was built in 2020 and out of frustration and money spent the car just sits and gets started a few times a year. The build I the original 98 ls1 with torquer v2 cam, Dorman ls2 intake, Holley 90 tb 243 heads and 60lb injectors. The tps and iac were put in new from the build and were ac Delco. The iac counts right now are at 102 and I cannot bring them down any lower or it will immediately surge. It will sit and idle fine until I driving it around and come to a stop. It is not every time but more times than not. I?m about to swap a stock engine in it as this point because I miss my car. Please help

This should be a easy setup to nail.. If it was VE tuned and the tuner is worth his salt.. but a worn out/sticky TPS sensor will cause the same symptoms. One that doesn't return to 0% TPS every time. A log would be really helpful.

[bk2life]

Please help

3 days later
and nothing

guess didnt need that much help after all

[edcmat-l1]

businessman-looking-into-crystal-ball.jpg


....... to the rescue!