On injectors, if you can obviousely wiggle the injectors in their mounts and they feel loose at all, then the o-rings need to be replaced.
Here's a story. I recently did this for a friend's kid (who owns a serious POS 16v) and he had one injector that was super loose. I just pulled it out by hand without any force at all. The "head" of the injector was missing and half the shroud was gone. Looking inside the injector hole with flashlight reveals said parts rattling around inside intake valve chamber. Holy crap. Using various dental tools and cuss words I got the stuff out of there, was like brain surgury. I also noticed residue from epoxy around the brass fitting that the injector mounts into. Somebody has been here before. Luckily nothing got into the engine and we replaced the shroud along with the o-rings. Car still runs like ass but at least I know what isn't is causing the problem. Rich Blake
