HP 1160 1320 manual tray 1 won't feed envelope or single page; sticking solenoid repair

If your HP 1160 or 1320 Laserjet won&properly feed from tray 1 (the manual slot) chances are you have a sticking solenoid. This is a common problem on many HP Laserjets. If you don&want to disassemble the printer, see my tip at approximately 7:39. Before I made this permanent repair, I found that tray 1 would work more reliably if you pulled out tray 2. This might work for you too. The HP 1160 has three solenoids and the tray 2 solenoid looks slightly different from the tray 1 solenoid which might explain why you only see the sticky residue and get the malfunction on just tray 1.