Previously posted 94 MT 55,000 miles has Code 16 stored. The Opti, Water Pump & O2's were replaced by the Chevy dealer at 49,000...6,000 miles ago. Driving on the local highway at 70+ mph in 6th gear when the the car shuts down. No Stumble or Hesitation before shut down.

Drove the car yesterday more than 100 miles, mostly highway, with no problems. Temp was 190 - 194. Later had some errands, all short trips, temp goes over 200 and the car shuts off. Turn the key of and it starts right up. As long as the car is moving and the temp is coming down it runs fine. Stop at a stop sign and it shuts off. Almost like it is heat related. The Check Engine light comes on only after the car shuts off, not before.

Could it be the Ignition Control Module or the coil or is the opti bad? Thanks,

Being temp related it sounds more like the ICM than anything else.

That is a strange nut to crack.

What is supposed to happen at +200°? Fans??? Something is supposed to happen at that temp...and when it tries to "happen" it hits a ground or a short and the thing kicks off....maybe to protect itself??

I'm just throwing things against the wall.

Back to: Did the mechanic clear the code?

"Could it be the Ignition Control Module or the coil or is the opti bad?"

It could be those, it could be other things. Anyone answering your question is just guessing.