1997 LX 450 with 214k miles. The problem is a bubbling sound behind the dashboard when I switch the heater on after driving for a while with the AC. Earlier, the gurgling sound would occur first thing in the morning as I pull of the driveway. But since then, I replaced all the heater hoses, radiator cap (OEM), overflow reservoir cap/hose, and 2 weeks ago, the heater valve because the plastic connectors (nipples) were worn out and pitted. This improved the situation and I don't have the early-morning gurgling any more, especially if I park overnight with the heater set to the ON position.
So now, the only time I hear gurgling is if I drive for a while with the AC on, then on an incline and under load switch on the heater.
It seems that air is seeping into the system when the car's hot and the heater valve is closed.
I do not lose coolant. It remains rock-steady over periods of months and thousands of miles. I did a chemical test for combustion gases in the coolant and got negative results.
I do have traces of oil seeping into the coolant and accumulating on the radiator cap and in the coolant reservoir. Engine runs great and compression is from 179-195. Does anyone have any pointers or advice where to look (besides replacing the head-gasket to solve the oil issue)?
So now, the only time I hear gurgling is if I drive for a while with the AC on, then on an incline and under load switch on the heater.
It seems that air is seeping into the system when the car's hot and the heater valve is closed.
I do not lose coolant. It remains rock-steady over periods of months and thousands of miles. I did a chemical test for combustion gases in the coolant and got negative results.
I do have traces of oil seeping into the coolant and accumulating on the radiator cap and in the coolant reservoir. Engine runs great and compression is from 179-195. Does anyone have any pointers or advice where to look (besides replacing the head-gasket to solve the oil issue)?