Originally Posted by BAVBMW

I don't think it's particularly applicable to this situation, as it sounds like you have a problem specific to one valve, but remember, either electrical or mechanical, a governer only affects the speed you can power the engine up to. If equipped with a manual transmission, one can always over-rev an engine by downshifting incorrectly.

I've seen several engines, both gas and diesel, destroyed in this manner. And each time the customer said "I thought the computer/governer would keep it from over-revving". Apparently they were under the impression that new control systems were not only able to control aspects of the vehicles engine and other systems, but able to control the laws of physics as well. While some new systems almost seem like it, flirt with the idea of it, none have managed to defy physics yet.

MV