2000 Catera Running hot

cassa63 · #1 (**permalink**) 07-04-09, 02:02 PM

2000 catera started running hot and causing oil light to come on. Should the cooling fan behind the radiator be on when the engine is running or only come on when triggered by temp? also when temp rises above the half way mark only one of the front fans(drivers side) comes on and the one behind the radiator? yesterday was stuck in traffic and temp rose causing the fans to kick on but the oil pressure dropped into the red due to the temp and the oil light came on. when I got going the oil pressure increases on acceleration but the oil light stayed on. Is the engine temp causing the oil to thin too much? what is up with the fans? could it be a relay issue, if so which relay(s)?

investor74 · #2 (**permalink**) 07-05-09, 01:20 AM

The cooling fans on the Catera (One primary and two secondary) are energized in a fairly complex pattern depending on the coolant temp. The primary fan can run with a resister for low speed, the secondary fans in series for half speed, the primary without the resister for full speed, and the secondary fans in parallel for full speed. This pattern is further changed when the AC is on. There are three temps in the pattern for without the AC and three with the AC.

Depending on the ambient temperature outside, the temperature gauge may temporarily overhsoot the halfway mark on a hot day before the fans kick in to bring it down. If you are using the 10W40 oil, slight overshooting should not cause any "thinning"

Are you getting a oil level light or the oil pressure indicator light? There are one of each. Your oil level can be low.

Barry

cassa63 · #3 (**permalink**) 07-05-09, 10:58 AM

Thanks Barry, the other day the outside temp was only about 70 degrees, and lately the engine temp as been running just slightly over half while driving, but sitting in traffic due to an accident the temp began to climb kicking the cooling fans on, but as I sat there the oil pressure began to drop as the engine temp went up and the pressure went into the red zone and the oil pressure light came on. When I finally got going the pressure increased with acceleration, however the oil pressure light stayed on. It's not the oil level as that is full and was just changed about a month ago. I drove home, about 20 miles, and checked the oil and it seemed awfully thin....any ideas? if this is happening at 70 degrees I can't imagine what will happen when it's 90 degrees outside...