S5 NA
Getting a light weight flywheel (9lb) soon and I was wondering if the reduction in inertia will occasionally cause my engine to stall at idle. I have idle issues once in a while where the idle will pulse from about 900rpm down to around 500rpm where it feels like it's on the verge of stalling. Turning on the vents sometimes stabilizes the idle and other things such as brakes and headlights will destabilize it. Anybody with similar idle issues have a problem with their lite fw?

 

I can't comment on whether it'd make your more likely to stall, but I can tell you that you should clean up all of the grounds on the car, as well as the battery terminals and positive wires at the main fuse. It's not that hard, but it could improve how your car reacts to electrical loads. It's not supposed to stall every time you turn a light on.

You also check the TPS to be sure it's adjusted properly.

 

The TPS was adjusted about a year ago and I've just replaced the battery connections and cleaned the grounds and I still have the same issues. I've decided to live with it because I think it's more annoying than it is detrimental to car health. Thanks for the advice though.

 

It might be worth it to open the air bypass screw all the way, or tighten the throttle cable to get the idle high enough that it won't stall. Unless you've already done this too.

You can also swap out the alternator with one from an FD to attempt to get a more stable electrical system.

 

Actually, it's never stalled yet due to idle issues, it just feels like it's going to stall. I'm just worried that with a lightweight flywheel, it will stall unless I keep a constant slightly open throttle.

 

If you adjust your dashpot properly it will not stall because the dashpot keeps the throttle plates from snapping shut. Dashpot adjustment is in the FSM... it's this mushroom looking thing on the TB.