RE: Mamba monster truggy elec problem
The BEC (battery elimination circuit) is built into the ESC. The ESC, therefore, powers the receiver. If the BEC is weak (which I've heard Mambas are) and your steering servo (which gets its power from the receiver) is a power hog like a Savox, it will cause problems. Either the servo will get twitchy, or the receiver "browns out" and can cause twitchy steering or throttle.
If you don't have another servo or receiver to try, it can be tough to find the root cause sometimes. And of course, since you are electric, you don't have a receiver battery lying around, but that would be a good thing to try if you can get yer hands on one. That would eliminate the BEC. If that solves the problem, then the issue IS the BEC. Get it?