by: PAUL BRAND
- Updated: February 8, 2013 - 11:02 PM
Q: Our ’93 Lumina minivan has the 3800 V6 engine. Fuel pressure is good when the key is turned on and while it warms up. As soon as it warms up, and I’m assuming goes into “closed loop” operation for fuel-air mixture calculations, the fuel pressure smoothly drops to zero over about 3 seconds. I’m assuming the computer is turning the fuel pump off. The factory manual doesn’t describe what inputs to the computer would cause it to shut down the in-tank fuel pump. My suspicions would point toward either the fuel pressure regulator or the oxygen sensor. Can you enlighten me?