Originally Posted by Windays

I think I'm done with this. I've spent hours trying to get this thing to just run stable going lean, going rich, starting over from factory settings. I've watched a ton of videos on tuning and 99% sure I'm, not doing anything wrong. I just can't find anything that works.

The idle screw does not change my idle speed at all, it just stays the same until I screw it in and it can't stay running. I've set it with feeler gauges to .7-1mm tried .7-.8-.9-1mm. Only way I can control my idle speed is with the LSN. The HSN is a turn and a half out from factory settings. If I start going in from that it runs hot and starts blowing glow plugs. It won't shift at WOT it just revs up and stays there, I have to slowly give it throttle through the powerband. This seemingly gets better if I start richening the HSN to a point. Checked throttle servo and 100% throttle is carb fully open and flush with the carb intake. Everything points to it running too lean, the tailpipe and the mess coming out the back say's waaaaay too rich and I'm blowing plugs which traxxas says means it's too rich but it will hit 300 F and smoke after 2-3 WOT passes if I start leaning it out. I keep trying to richen it but I don't want to just keep going and going. Conversely, leaning it out like I said blows plugs and I don't want to buy glow plugs every 2 tanks which is about what it's averaging. I make very small changes, 1/8-1/16th a turn at a time and do a couple passes.

forgot to add it seems to want to move on it's own and If I lift the truck the wheels will spin like crazy and the engine revs up pretty good. I have to richen the LSN so it doesn't do that because the idle screw does not change the idle speed at all.

Also this was a brand new truck and I did the break in process with the Traxxas factory settings which seem to be too lean but are actually supposed to be very very rich. I've also only used the Traxxas top fuel, 20% to break it in plus 5 more tanks and now I switched to 33%.