Cadillac Repair: 98 sts overheating, head gasket problem, camel mode


Question
Thanks, When I blow air into the cylinders do  I need a adapter or is it ok to just blow air into the cylinders?
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-----Question-----
Hi, recently the check engine light went on and the car was running poorly, a new egr was put in. My mechanic said more error codes were present and reset them saying lets see what happens. The car ran better, however it now over heats and 2xs went in to "camel" mode, I brought it back and the thermostat was replaced. The car is still over heating,I notice the fans only come on when the car is running hot (past 3 o'clock on the temp gauge), I removed the over flow cover, ran the car for 10 minutes, no bubbles were present in the reserve. I hear water gurgling inside the car when I first accelerate. I checked for wet spots on both the driver and passenger side floors and none were present. The cars heat works fine unless it begins to run hot and over heats. I have to replace dextron after the car overheats. I have checked under the car for leaks and have not seen any thing, except for steam escaping from the overflow tank cover when it over heats. What should;d be the next course of actions? Thanks
-----Answer-----
With the engine at normal operating temp, Put 80 lbs of compressed shop air into each engine cylinder one at a time via the spark plug hole and look for rdiator bubbles which would indicate a head gasket problem.

Answer
As long as you can maintain a good seal around the spark plug hole you can use whatever you want.

The easiest thing to use is a compression gage hose, Remove the schrader valve from the bottom of the hose and attach an air hose in place of the gage.