engine problems-1986 300e
 

My 300e has 110,000 miles-it runs fine until it gets hot. it then knocks hard and quits running. It does not start up again. I checked the compression. It is between 140 & 150. The chain has been replaced. It looks good and tight. When it starts cold it runs smooth with plenty of power. Any suggestions?

These engines need 91 octane fuel, this sounds like ignition timing too far advanced, I would check that first

What does "hot" mean? What is the temp gage reading when the problem starts? By "knocks" do you mean detonation? What fuel grade are you using? What is your current ambient temperature range?

The EZL module reduces spark timing under most load conditions if the temp exceeds 95C, but idle timing is fixed at the value listed on the tuneup/emission decal, which is probably 9 degrees.

Duke