Cadillac Seville / Cadillac Eldorado Forum Discussion, 2001 Seville coolant into the oil in Past Cadillac Vehicle Discussion; Good Evening and thanks for reading.
I have a 2001 Seville STS that is dumping the coolant into the oil.
I have all of the classic symptoms of what would be blown head gasket.
Coolant level dropping without leaking.
"Oil" level rising on the dipstick.
Very steamy exhaust that smells sickly sweet.
Lots of pressure in COLD cooling system.
It's not that the oil/coolant mixing does NOT occur: it's not common, so it's usually not the first indicator of failed head gaskets in these engines..........BUT you seem to have an uncommon problem.
Your pressure in the coolant reservoir is telling - now you need to perform a cylinder block exhaust gas test. Either rent the system/buy the fluid at a large parts store or go here: www.sjdiscounttools.com/lis75500.html.
With your other indicators, if you choose to overhaul (not top overhaul) the engine, use head/cylinder block studs or Norm's inserts.
ALSO common if the radiator has an internal crack and coolant find its way into the oil passages, and this IS a common issue.
Only if the car has an engine oil cooler, and unless his STS has the V03 HD cooling RPO, the car doesn't have one. Transmission fluid cooler leaks are more common.
thebigtomster, Look on the RPO (Regular Production Option) sticker under the spare tire cover - is there a code "V03" in the sequence ? If there is, then the car has HD cooling and an engine oil cooler, and that would be another place to investigate. 2 oil lines coming from the oil filter adapter and snaking around to the front, top and bottom, of the passenger side radiator end tank.
To find out what is built into your car, enter the VIN into the box in www.compnine.com .
If you are truly getting engine oil in the coolant, you must have a catastrophic head bolt thread failure: The oil from the cam area drains back to the oil pan through 3 drain wells in each head, down through the block to the oil pan gasket seam. It is possible - possible - that one or more of those drains - which go through the head gaskets - are severely compromised.