When I idle at stop lights, sometimes the engine in my k5 will shudder erratically. When it shudders, I hear a clicking noise near the master cylinder. This happens more when in drive than park, and also seems to happen more the warmer it is outside (coincidence?). /forums/images/graemlins/confused.gif Once in a while, when accelerating it will happen quite a bit, especially if it was really bad the last time it was idling. I have replaced the dist. cap and rotor. The plugs and wires look good too. Any ideas? Thanks in advance! PS - Can't pull codes until the cable arrives to use with winaldl. Check engine light is out too.