Cooling Issues

Vehicle-

1998 Nissan 200SX SE-R

114000 miles



Yesterday I was driving home when my car started overheating so I pulled over and popped the hood to find the radiator reservoir boiling and white smoke under the hood. I let the car cool down so I could drive it home to look at, but on the way my car dropped from 2500rpm to under 2000rpm and if I tried to accelerate the car would start lurching forward and the tachometer went crazy. So I slowed down to keep the car stable. When I got home to check the car out further the radiator fluid was boiling again. I did a test to check for exhaust gases in the radiator, but that came back negative. I have also replaced the thermostat and made sure the water pump was functioning. However, today when refilling the radiator with water to check the system again little bubbles started coming up and my friend said it was from a blown head gasket, which is weird from it passing the test exhaust test gas test yesterday, and the car is still heating up very rapidly. So my problems are:



Rapid overheating

Won’t function over 2000rpm

Gases in the radiator



And I have already:



Checked radiator cap

Checked for leaks

Changed thermostat

Checked water pump (functioning)





- If the head gasket is blown is the cause of my problems or result from the overheating?

- What is with the rpm problem?

-Is there something else I should check before adding block sealant?

It sounds like a blown head gasket if there’s bubbles in the coolant and the engine overheats very quickly. The RPM’s drop because the engine is overheating causing the engine oil to break down and the engine is starting to sieze up. Also check the oil for coolant contamination.

Because the RPM’s dropped because of the engine siezing up, there may now be more damage to the engine besides the blown head gasket.

Tester