2002 Trailblazer with 165K. All of a sudden when engine is warm and at idle, the oil pressure drops from 40-60 to 0 psi and get shut off engine warning. This does not happen all the time when engine is warm only say after having driven on highway for a while. Put in neutral give a little gas, pressure goes back up and then slowly back down. See this problem all over the web but no clear cut solution. Have considered putting on gauge to check pressure but as I have said it does not happen when engine is warm and idling (typically reads 40). Have changed out oil sensor, cleaned throttle body and done full tune-up. Engine idles steady at 600. Have also changed out CAM position sensor and solenoid. None of this has made any difference. Any ideas

 

Putting in a mechanical gauge will tell you if the pressure is actually dropping or if it is an electrical malfunction. You need to find out because if the pressure is dropping, you risk blowing the engine!

 

Where would I tap a mechanical gauge in. Also, could you direct me the type gauge that you are talking about. Just using a pressure tester doe not do me any good as I can not replicate conditions.