LS1 Racing

iTrader: (15)

Hi Everyone,

I'm very new to the tuning world, and have an issue to resolve on my swapped car.

Vehicle is a 2002 Camaro with an LQ4 block, LS3 heads and intake, and a Comp cam with the following specs: Duration: 223, 231; Lift: 610, 617; LCA 112. The shop that did the upgrades got the tuning dialed in for part-throttle and WOT, and the car runs like an animal. The only issue remaining is that when the car is warmed up and I'm coasting up to, and stopping, the idle will go up to 1800-2000 RPMs and will stay there for several seconds after I've stopped. It was even worse before this weekend, and my tuner took a swing at it to get it down to where I have described above. Since my tuner is very far away and very busy, I don't want to keep bothering him with this, so I'd like to try to solve it myself.

Attached is a log, as well as the current tune. I made some adjustments to the throttle cracker table, changing all values to 2.2 in the 0-1600 RPM range, and that seemed to slightly shorten the wait time for the idle to drop down to around 975 RPM. This was versus the previous values of 1.1 in those cells.

Before I start messing around with anything else, I really wanted to get some input, so any help would be greatly appreciated.

NW Iowa WS6

iTrader: (9)

I just had a thread very similar to your issues, my tps sensor was bad, may not be yours but for $30 bucks I got my car back, hopefully yours is this simple

LS1 Racing

iTrader: (15)

After trying several different suggestions, I wound up I disabling the Throttle Cracker and the problem is completely gone. I am noticing a few, very subtle drivability issues like some minor surging at low speeds, and it drops into open-loop on decel very easily, but when i put the clutch in, the idle soft lands at just around 1000-1100 or so every time, before settling in at about 950-975.

I'm just glad to have the hanging problem behind me.

danieloneil01

Have you searched for the throttle cracker thread on hptuners? Someone made a scanner log on what to log and to use when changing the throttle cracker table.

LS1 Racing

iTrader: (15)

Yes, I did do that. I made the suggested adjustments and still had the problem.

I started a similar thread over there, though, and the feedback I'm getting is that it's the follower table that's really causing the original issue, and that by disabling the Cracker Table, I've caused some drivability issues, too.