Coolant/Rad info

[cowboy1sf]

Low coolant can mean a hotter engine. Once the petrol gets above a certain temperature it can cause detonation/pinging regardless of timing being correct etc. due to the nature and design of these Pontiac engines and electrics it's more common than you think. The temperature switch or sender is located high on one of the cylinder heads, and with no coolant level sensor the level can drop low inside the radiator without any signs. The water pump will then Struggle to pump the lower volume of coolant to the higher parts of the engine where the sender is. The sender can give a reading to the gauge which shows normal or even low as only the block heat conducts to the sensing tip, but in reality the coolant passage is only full of air and no water surrounds the sensing tip. You can then overheat the engine without even knowing it.

Although not on a Pontiac, I've done this on a ford focus! Gauge read normal, never bothered checking the level As it never leaked or used coolant. Started pinking early on and by the time I got a few miles from home the engine lost performance rapidly and started to smell funny. Pulled over to find a practically empty cooling system with no warning whatsoever.

Ian