1992 Chevy Suburban hissing noise after i turn off motor un

Obviously, without hearing the noise, I can't tell you exactly what it is. Did the noise quit by itself after a second or two, or what happened? If you were to go out now, start and drive the truck now, would the noise be back? Please advise.

No the noise continues whether the truck is on or off. My wife just left in the Suburban and the noise is still on. When I turn the truck off it continues. Not being a mechanic it is hard to say where its coming from. Its not from the engine but from underneath the carriage. It stayed on for over an hour and does not turn off. It sounds like a small motor and its not from the seats or anything inside the truck but underneath. The traction light and abs lights are the only ones that stay on when the truck is on. Of course they go off when I turn the engine off.

Is the noise coming from the fuel tank? You're sure it's not coming from under thr hood?

Actually it's not a hissing noise but more of a "like your motor is still on" noise. It is not the gas tank or the motor area. I got down and touch some parts down there with a screw driver just to see if I could isolate the noise and there are a couple of parts that seem to be attached to the undercariage and adjoined to the frame and have some metal lines hooked up to it. The noise seems to be generating from their. It's like the catalytic converter is still on and some gadget that has a flow does not stop. Why would the ABS and Traction Control lights stay on when I am driving?

OK, what you are hearing is the ABS pump running which is indicitive of a pressure switch failure. The true diagnosis need to be done on a computer scan unit with ABS capability. It will have to be "hooked up" to an anallizer. You may want to pull the ABS fuse, or you may have a dead battery come morning.

Where is the ABS fuse located? Wouldn't it be easier to disconnect the battery. I know what that looks like.

Thanks

The ABS fuse should be #2 in the underhood fuse block.

I did find it and removed the ABS Fuse and the ABS Pump stopped. Thank you. I will replace the fuse and hopefully this will cure the problem.

Replacing the fuse will solve your problem. James to you to pull the fuse to prevent your battery from being drained by the faulty ABS motor. You need to have the ABS motor serviced/repaired/replaced.