1999 suburban gage oil pressure is 0 when it warms up. rpm drop to 3-4 rpm when oil pressure goes to 0. Sounds good, runs excellent -no noise. Actually it sound better then most new cars. It is so unnerving I shift to neutral and rev to 7 hundred at red lights. That brings the oil pressure up to 20. Any suggestions would be appreciated.

Johnny Massengill

• 345 Answers
• Posted on Nov 10, 2008

SOURCE: OIL PRESSURE LIGHT COMES ON AND PRESSURE GOES TO 0 ON GAUGE

Any time the oil pressure is 0 you take a chance of locking up the motor. The only way to know for sure is to put a pressure gauge in the oil pressure sending unit port on the engine and see what the pressure really is. At that point you will either have the peace of mind in the knowledge that the sending unit is really bad and needs replacement or you can then contact a repair shop and tell them what your testing has revealed. I wouldn't drive or run your truck while the oil pressure is at zero.

Good luck

SOURCE: oil pressure drops once it gets warm

Sorry to say it sounds like the motor is gone. Higher oil pressure when the oil is cold is normal. But, when the engine gets to operating temp and the pressure bottoms out and the engine knocks you have big problems. If the mileage is very high (150,000) or more your bearings are so worn that the oil can't fill the void between the surfaces and thus the low oil pressure.

SOURCE: 2006 Yukon Denali, oil pressure gauge malfunction

Most likely the oil pressure sensor is bad. Its located in the very rear of engine on top of bell housing area.

Ronny Bennett Sr.

• 6988 Answers
• Posted on Nov 15, 2009

SOURCE: 1995 k2500 suburban idle too fast

replace the coolant temp sensor,it`s values are off,it is defective.Also if this does not work,witch I think It will,change the throttle position sensor.

SOURCE: My oil pressure gage just drops to 0!!!

My Envoy does the same thing..Had the sender replaced last winter when it was doing it. Went all summer with perfect pressure and as soon as the outside temp hit <30 degrees the pressure is dropping again..Curious as to why every time the temp gets below 30 I keep having this issue. If I shut the car off and turn it right back on it jumps to normal stays for a while then drops, shut it off and right back on (no wait) goes back to normal...Only when cold outside.... Confused!