First i have a question — what is the factory purpose of the top clutch switch? AFAIK its purpose in other cars is to cancel cruise control. We do not have that. Are there any other factory purposes (i'm not talking about Tephra's nlts here)

Reason why i ask is, when my car is cold, if i rev the engine right after pushing the clutch (therefore disengaging the top clutch switch) my IPW gets cut in half (i.e whithout touching the clutch it's ~8ms, after pushing the clutch it's only ~5ms) and as a result my AFR go super lean (over 21) and as a result of that my revs fall and i get a stumble. This is annoying as hell when driving the car cold. (This behavior continues on a warm car but IPW gets cut less, so it's not noticeable for driving.)

Since no one else seems to have this issue, so i'm assuming this most likely isnt a bug with Tephra patch (im using the latest 5.10 94170015), but something else.

So main question is — what happens in the ECU when the top clutch disengages, why IPW gets reduced (cruise control feature?) and how can this be fixed??

For now i just disconnected the top clutch switch and the problem is fixed, but i would like to continue using NLTS, so... please help!!

 

launch control?

 

Along these lines why does pushing the clutch in help the throttle hang issue. Clutch far enough in to trip switch not to disengage clutch disc itself. Any ideas? I was wondering about the periphery for the clutch switch could the bit simply be changed from 1 to 0 or 0 to 1 to turn this off? Don't non US cars only run one switch?

PS not trying to thread jack but might help OP

 

Most ECU's tie the clutch switch into both idle control and decel fuel cut control. Sometimes, clutch in = no decel fuel cut, and it is also sometimes used to decide when to take the idle control from open to closed loop when the vehicle is moving.