I'm at a idle speed in drive or park, it sometimes acts like is wants to die. Does this little chugging noise and shake.. I took it to the shop and they told me I needed new spark plugs and wires. After replacing them, the problem seems to be happening more often. The problem is there isn't a check engine light that comes on. Also, my head gasket went out last summer, so that was just replaced along with the radiator. Just so you know some history on this car. Any ideas would help.