I have a 89 F150 Lariat with a 4.9 L engine. Sometimes my Fuel Pump continues to run after the engine is turned off and will completely drain the battery. The other day as I walked by the truck I noticed the fuel pump was running and sure enough the battery was dead. Only this time the truck hadn't been run for three or four days. Does anyone have any ideas on what may be happening? This has gone way past annoying.

 

its the fuel pump relay sticking on. its under the hood. no big deal. locate the fuel pump relay. when its running tap on it a little. it should turn off. no big deal to fix, (change) good luck