Excessive pinging when driving on hot days

[virafp]

On my 81 320i, when it runs at around the half mark or slightly higher on the water temp gauge, it starts to ping excessively, even on a slight uphill - is this normal in hotter temeratures? We have had a few abnormally hot days, and I just noticed this driving yesterday and today.

Any suggestions would be welcome.

Thanks

Viraf

[blitzed310]

No not normal. Its only been 95 degrees or so, hardly that hot. How many miles on the motor? Mine did this for a while then lost compression across the cylinders, it went from a mild knock to an oh shit knock in a matter of a few weeks. Its shouldnt be going past the 1/2 way mark on the gauge either, warping can be arise from this over time too. An electric fan solved this issue for me and it never sees past the second mark, even if I let it sit all day.